diff --git a/.circleci/config.yml b/.circleci/config.yml
index c5f9a1781d4f..8258aba3330e 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -71,7 +71,7 @@ jobs:
     steps:
       - checkout
       - run:
-          name: Sync with latest master branch (only on PRs)
+          name: Sync with latest main branch (only on PRs)
           command: |
             if [ -n "$CIRCLE_PULL_REQUEST" ]
             then
@@ -92,8 +92,8 @@ jobs:
             npm i tap-mocha-reporter --save-dev
             node lib/download-node
       - run:
-          name: Download master branch Test262 artifact
-          command: node lib/download-master-artifact ~/master.tap
+          name: Download main branch Test262 artifact
+          command: node lib/download-main-artifact ~/test262-main.tap
           <<: *test262_workdir
       - run:
           name: Run Test262
@@ -106,10 +106,10 @@ jobs:
             cat ~/test262.tap | $(npm bin)/tap-mocha-reporter spec || true
           <<: *test262_workdir
       - run:
-          name: Compare previous master branch & current job results
+          name: Compare previous main branch & current job results
           command: |
             mkdir -p ~/test-results/test262
-            node lib/compare-results ~/master.tap ~/test262.tap | tee ~/diff.tap
+            node lib/compare-results ~/test262-main.tap ~/test262.tap | tee ~/diff.tap
           <<: *test262_workdir
       - store_artifacts: *artifact_test262_diff_tap
       - run:
@@ -171,28 +171,36 @@ workflows:
   build-standalone:
     jobs:
       - build-standalone
-  test262-master:
+  test262:
     jobs:
       - test262:
           filters:
             branches:
               only:
-                - master
-  test262:
+                - main
+                - next-8-dev
+                - next-8-rebased
+  test262-pr:
     jobs:
       - approve-test262-run:
           type: approval
           filters:
             branches:
               ignore:
+                - main
                 - master
+                - next-8-dev
+                - next-8-rebased
       - test262:
           requires:
             - approve-test262-run
           filters:
             branches:
               ignore:
+                - main
                 - master
+                - next-8-dev
+                - next-8-rebased
   e2e:
     jobs:
       - publish-verdaccio
diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index f805376b4926..fc20dd4d88b6 100644
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -1,6 +1,6 @@
 <!--
 Before making a PR, please read our contributing guidelines
-https://github.com/babel/babel/blob/master/CONTRIBUTING.md
+https://github.com/babel/babel/blob/main/CONTRIBUTING.md
 
 Please note that the Babel Team requires two approvals before merging most PRs.
 
diff --git a/.gitpod.yml b/.gitpod.yml
index d879777d1390..ffc1d77a0029 100644
--- a/.gitpod.yml
+++ b/.gitpod.yml
@@ -24,7 +24,7 @@ tasks:
 github:
   # https://www.gitpod.io/docs/prebuilds/#configure-prebuilds
   prebuilds:
-    master: true
+    master: true # enable for the default branch (even if it's not named "master")
     branches: true
     pullRequests: true
     pullRequestsFromForks: true
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 1602f548b04c..1732a798c2cf 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -16,15 +16,15 @@
 
 # Contributing
 
-Contributions are always welcome, no matter how large or small! Before contributing, please read the [code of conduct](https://github.com/babel/babel/blob/master/CODE_OF_CONDUCT.md).
+Contributions are always welcome, no matter how large or small! Before contributing, please read the [code of conduct](https://github.com/babel/babel/blob/main/CODE_OF_CONDUCT.md).
 
 If you want an already configured online IDE to contribute to Babel, you can use [Gitpod](https://gitpod.io/#https://github.com/babel/babel)!
 
 ## Not sure where to start?
 
 - If you aren't just making a documentation change, you'll probably want to learn a bit about a few topics.
-  - [ASTs](https://en.wikipedia.org/wiki/Abstract_syntax_tree) (Abstract Syntax Tree): The Babel AST [spec](https://github.com/babel/babel/blob/master/packages/babel-parser/ast/spec.md) is a bit different from [ESTree](https://github.com/estree/estree). The differences are listed [here](https://babeljs.io/docs/en/next/babel-parser.html#output).
-  - Check out [`/doc`](https://github.com/babel/babel/tree/master/doc) for information about Babel's internals
+  - [ASTs](https://en.wikipedia.org/wiki/Abstract_syntax_tree) (Abstract Syntax Tree): The Babel AST [spec](https://github.com/babel/babel/blob/main/packages/babel-parser/ast/spec.md) is a bit different from [ESTree](https://github.com/estree/estree). The differences are listed [here](https://babeljs.io/docs/en/next/babel-parser.html#output).
+  - Check out [`/doc`](https://github.com/babel/babel/tree/main/doc) for information about Babel's internals
   - Check out [the Babel Plugin Handbook](https://github.com/thejameskyle/babel-handbook/blob/master/translations/en/plugin-handbook.md#babel-plugin-handbook) - core plugins are written the same way as any other plugin!
   - Check out [AST Explorer](http://astexplorer.net/#/scUfOmVOG5) to learn more about ASTs or make your own plugin in the browser
 - When you feel ready to jump into the Babel source code, a good place to start is to look for issues tagged with [help wanted](https://github.com/babel/babel/labels/help%20wanted) and/or [good first issue](https://github.com/babel/babel/labels/good%20first%20issue).
@@ -106,7 +106,7 @@ If you just want to run all tests:
 $ make test-only
 ```
 
-When working on an issue, you will most likely want to focus on a particular [packages](https://github.com/babel/babel/tree/master/packages). Using `TEST_ONLY` will only run tests for that specific package.
+When working on an issue, you will most likely want to focus on a particular [packages](https://github.com/babel/babel/tree/main/packages). Using `TEST_ONLY` will only run tests for that specific package.
 
 ```sh
 $ TEST_ONLY=babel-cli make test
@@ -137,7 +137,7 @@ To enable the Node.js debugger added in v6.3.0, set the `TEST_DEBUG` environment
 $ TEST_DEBUG=true make test
 ```
 
-You can combine `TEST_DEBUG` with `TEST_GREP` or `TEST_ONLY` to debug a subset of tests. If you plan to stay long in the debugger (which you'll likely do!), you may increase the test timeout by editing [test/mocha.opts](https://github.com/babel/babel/blob/master/test/mocha.opts).
+You can combine `TEST_DEBUG` with `TEST_GREP` or `TEST_ONLY` to debug a subset of tests. If you plan to stay long in the debugger (which you'll likely do!), you may increase the test timeout by editing [test/testSetupFile.js](https://github.com/babel/babel/blob/main/test/testSetupFile.js).
 
 To overwrite any test fixtures when fixing a bug or anything, add the env variable `OVERWRITE=true`
 
@@ -165,26 +165,26 @@ In case you're locally getting errors which are not on the CI, it may be due to
 
 ### Writing tests
 
-Most packages in [`/packages`](https://github.com/babel/babel/tree/master/packages) have a `test` folder, however some tests might be in other packages or in [`/packages/babel-core`](https://github.com/babel/babel/tree/master/packages/babel-core/test/fixtures).
+Most packages in [`/packages`](https://github.com/babel/babel/tree/main/packages) have a `test` folder, however some tests might be in other packages or in [`/packages/babel-core`](https://github.com/babel/babel/tree/main/packages/babel-core/test/fixtures).
 
 #### `@babel/plugin-x`
 
 All the Babel plugins (and other packages) that have a `/test/fixtures` are written in a similar way.
 
-For example, in [`@babel/plugin-transform-exponentiation-operator/test`](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-exponentiation-operator/test):
+For example, in [`@babel/plugin-transform-exponentiation-operator/test`](https://github.com/babel/babel/tree/main/packages/babel-plugin-transform-exponentiation-operator/test):
 
-- There is an `index.js` file. It imports our [test helper](https://github.com/babel/babel/tree/master/packages/babel-helper-plugin-test-runner). (You don't have to worry about this).
-- There can be multiple folders under [`/fixtures`](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures)
+- There is an `index.js` file. It imports our [test helper](https://github.com/babel/babel/tree/main/packages/babel-helper-plugin-test-runner). (You don't have to worry about this).
+- There can be multiple folders under [`/fixtures`](https://github.com/babel/babel/tree/main/packages/babel-plugin-transform-exponentiation-operator/test/fixtures)
 
-  - There is an [`options.json`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/options.json) file whose function is similar to a `.babelrc` file, allowing you to pass in the plugins and settings you need for your tests.
+  - There is an [`options.json`](https://github.com/babel/babel/blob/main/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/options.json) file whose function is similar to a `.babelrc` file, allowing you to pass in the plugins and settings you need for your tests.
   - For this test, we only need the relevant plugin, so it's just `{ "plugins": ["@babel/plugin-transform-exponentiation-operator"] }`.
   - If necessary, you can have an `options.json` with different options in each subfolder.
 
 - In each subfolder, you can organize your directory structure by categories of tests. (Example: these folders can be named after the feature you are testing or can reference the issue number they fix)
 - Generally, there are two kinds of tests for plugins
-    - The first is a simple test of the input and output produced by running Babel on some code. We do this by creating an [`input.js`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/input.js) file and an [`output.js`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/output.js) file. This kind of test only works in sub-subdirectories of `/fixtures`, i.e. `/fixtures/exponentian-operator/binary/input.js` and **not** `/fixtures/exponentian-operator/input.js`.
+    - The first is a simple test of the input and output produced by running Babel on some code. We do this by creating an [`input.js`](https://github.com/babel/babel/blob/main/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/input.js) file and an [`output.js`](https://github.com/babel/babel/blob/main/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/output.js) file. This kind of test only works in sub-subdirectories of `/fixtures`, i.e. `/fixtures/exponentian-operator/binary/input.js` and **not** `/fixtures/exponentian-operator/input.js`.
   - If you need to expect an error, you can ignore creating the `output.js` file and pass a new `throws` key to the `options.json` that contains the error string that is created.
-  - The second and preferred type is a test that actually evaluates the produced code and asserts that certain properties are true or false. We do this by creating an [`exec.js`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/comprehensive/exec.js) file.
+  - The second and preferred type is a test that actually evaluates the produced code and asserts that certain properties are true or false. We do this by creating an [`exec.js`](https://github.com/babel/babel/blob/main/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/comprehensive/exec.js) file.
 
 In a fixture test, you simply write out the code you want to transform in `input.js`.
 
@@ -310,16 +310,16 @@ Note that the code shown in Chrome DevTools is compiled code and therefore diffe
 
 - Create a new issue that describes the proposal (ex: [#538](https://github.com/babel/babylon/issues/538)). Include any relevant information like proposal repo/author, examples, parsing approaches, meeting notes, presentation slides, and more.
 - The pull request should include:
-  - [ ] An update to the [plugins](https://github.com/babel/babel/tree/master/packages/babel-parser#plugins) part of the readme. Add a new entry to that list for the new plugin flag (and link to the proposal)
-  - [ ] If any new nodes or modifications need to be added to the AST, update [ast/spec.md](https://github.com/babel/babel/blob/master/packages/babel-parser/ast/spec.md)
+  - [ ] An update to the [plugins](https://github.com/babel/babel/tree/main/packages/babel-parser#plugins) part of the readme. Add a new entry to that list for the new plugin flag (and link to the proposal)
+  - [ ] If any new nodes or modifications need to be added to the AST, update [ast/spec.md](https://github.com/babel/babel/blob/main/packages/babel-parser/ast/spec.md)
   - [ ] Make sure you use the `this.hasPlugin("plugin-name-here")` check in the babel parser so that your new plugin code only runs when that flag is turned on (not default behavior)
   - [ ] Add failing/passing tests according to spec behavior
 - Start working about the Babel transform itself!
 
 ## Internals
 
-- AST spec ([babel-parser/ast/spec.md](https://github.com/babel/babel/blob/master/packages/babel-parser/ast/spec.md))
-- Versioning ([doc/design/versioning.md](https://github.com/babel/babel/blob/master/doc/design/versioning.md))
-- Monorepo ([doc/design/monorepo.md](https://github.com/babel/babel/blob/master/doc/design/monorepo.md))
-- Compiler environment support ([doc/design/compiler-environment-support.md](https://github.com/babel/babel/blob/master/doc/design/compiler-environment-support.md))
-- Compiler assumptions ([doc/design/compiler-assumptions.md](https://github.com/babel/babel/blob/master/doc/design/compiler-assumptions.md))
+- AST spec ([babel-parser/ast/spec.md](https://github.com/babel/babel/blob/main/packages/babel-parser/ast/spec.md))
+- Versioning ([doc/design/versioning.md](https://github.com/babel/babel/blob/main/doc/design/versioning.md))
+- Monorepo ([doc/design/monorepo.md](https://github.com/babel/babel/blob/main/doc/design/monorepo.md))
+- Compiler environment support ([doc/design/compiler-environment-support.md](https://github.com/babel/babel/blob/main/doc/design/compiler-environment-support.md))
+- Compiler assumptions ([doc/design/compiler-assumptions.md](https://github.com/babel/babel/blob/main/doc/design/compiler-assumptions.md))
diff --git a/README.md b/README.md
index 8fd06702ce7a..472558348f0a 100644
--- a/README.md
+++ b/README.md
@@ -16,9 +16,9 @@
   <a href="https://www.npmjs.com/package/babel-core"><img alt="v6 npm Downloads" src="https://img.shields.io/npm/dm/babel-core.svg?maxAge=43200&label=v6%20downloads"></a>
 </p>
 <p align="center">
-  <a href="https://travis-ci.com/babel/babel"><img alt="Travis Status" src="https://img.shields.io/travis/com/babel/babel/master.svg?label=travis&maxAge=43200"></a>
-  <a href="https://circleci.com/gh/babel/babel"><img alt="CircleCI Status" src="https://img.shields.io/circleci/project/github/babel/babel/master.svg?label=circle&maxAge=43200"></a>
-  <a href="https://codecov.io/github/babel/babel"><img alt="Coverage Status" src="https://img.shields.io/codecov/c/github/babel/babel/master.svg?maxAge=43200"></a>
+  <a href="https://travis-ci.com/babel/babel"><img alt="Travis Status" src="https://img.shields.io/travis/com/babel/babel/main.svg?label=travis&maxAge=43200"></a>
+  <a href="https://circleci.com/gh/babel/babel"><img alt="CircleCI Status" src="https://img.shields.io/circleci/project/github/babel/babel/main.svg?label=circle&maxAge=43200"></a>
+  <a href="https://codecov.io/github/babel/babel"><img alt="Coverage Status" src="https://img.shields.io/codecov/c/github/babel/babel/main.svg?maxAge=43200"></a>
   <a href="https://slack.babeljs.io/"><img alt="Slack Status" src="https://slack.babeljs.io/badge.svg"></a>
   <a href="https://twitter.com/intent/follow?screen_name=babeljs"><img alt="Follow on Twitter" src="https://img.shields.io/twitter/follow/babeljs.svg?style=social&label=Follow"></a>
 </p>
@@ -75,7 +75,7 @@ Babel is a tool that helps you write code in the latest version of JavaScript. W
 });
 ```
 
-Try it out at our [REPL](https://babeljs.io/repl/build/master#?code_lz=NoRgNATGDMC6B0BbAhgBwBQDsAEBeAfNjgNTYgCUA3EA&lineWrap=true&presets=es2015%2Ces2016%2Ces2017&version=7.0.0-beta.2).
+Try it out at our [REPL](https://babeljs.io/repl/build/main#?code_lz=NoRgNATGDMC6B0BbAhgBwBQDsAEBeAfNjgNTYgCUA3EA&lineWrap=true&presets=es2015%2Ces2016%2Ces2017&version=7.0.0-beta.2).
 
 ## FAQ
 
diff --git a/doc/ast/spec.md b/doc/ast/spec.md
index 4c8ab28689cb..5c5b07d734db 100644
--- a/doc/ast/spec.md
+++ b/doc/ast/spec.md
@@ -1 +1 @@
-The [AST specification](https://github.com/babel/babel/blob/master/packages/babel-parser/ast/spec.md) has been moved to the babel parser package, `packages/babel-parser`.
+The [AST specification](https://github.com/babel/babel/blob/main/packages/babel-parser/ast/spec.md) has been moved to the babel parser package, `packages/babel-parser`.
diff --git a/eslint/babel-eslint-parser/README.md b/eslint/babel-eslint-parser/README.md
index a70cb1c721db..75814be5c1f4 100644
--- a/eslint/babel-eslint-parser/README.md
+++ b/eslint/babel-eslint-parser/README.md
@@ -1,4 +1,4 @@
-# @babel/eslint-parser [![npm](https://img.shields.io/npm/v/@babel/eslint-parser.svg)](https://www.npmjs.com/package/@babel/eslint-parser) [![travis](https://img.shields.io/travis/babel/@babel/eslint-parser/master.svg)](https://travis-ci.org/babel/@babel/eslint-parser) [![npm-downloads](https://img.shields.io/npm/dm/@babel/eslint-parser.svg)](https://www.npmjs.com/package/@babel/eslint-parser)
+# @babel/eslint-parser [![npm](https://img.shields.io/npm/v/@babel/eslint-parser.svg)](https://www.npmjs.com/package/@babel/eslint-parser) [![travis](https://img.shields.io/travis/babel/@babel/eslint-parser/main.svg)](https://travis-ci.org/babel/@babel/eslint-parser) [![npm-downloads](https://img.shields.io/npm/dm/@babel/eslint-parser.svg)](https://www.npmjs.com/package/@babel/eslint-parser)
 
 
 ## This project is still experimental and will be released with Babel v8. You can track our progress [here](https://github.com/babel/babel/issues/10752)! Please use [babel-eslint](https://github.com/babel/babel-eslint) in the meantime.
@@ -18,7 +18,7 @@ ESLint allows for the use of [custom parsers](https://eslint.org/docs/developer-
 transformed into an [ESTree](https://github.com/estree/estree)-compliant structure that ESLint can understand. All location info such as line numbers,
 columns is also retained so you can track down errors with ease.
 
-**Note:** ESLint's core rules do not support experimental syntax and may therefore not work as expected when using `@babel/eslint-parser`. Please use the companion [`@babel/eslint-plugin`](https://github.com/babel/babel/tree/master/eslint/babel-eslint-plugin) plugin for core rules that you have issues with.
+**Note:** ESLint's core rules do not support experimental syntax and may therefore not work as expected when using `@babel/eslint-parser`. Please use the companion [`@babel/eslint-plugin`](https://github.com/babel/babel/tree/main/eslint/babel-eslint-plugin) plugin for core rules that you have issues with.
 
 ## Usage
 
diff --git a/eslint/babel-eslint-parser/package.json b/eslint/babel-eslint-parser/package.json
index 36218eb13c84..39f9018609a4 100644
--- a/eslint/babel-eslint-parser/package.json
+++ b/eslint/babel-eslint-parser/package.json
@@ -13,7 +13,7 @@
   "bugs": {
     "url": "https://github.com/babel/babel/issues"
   },
-  "homepage": "https://github.com/babel/babel/tree/master/eslint/babel-eslint-parser",
+  "homepage": "https://babeljs.io/",
   "engines": {
     "node": ">=10.9"
   },
diff --git a/eslint/babel-eslint-plugin-development/package.json b/eslint/babel-eslint-plugin-development/package.json
index d59704a25597..5914c17606b3 100644
--- a/eslint/babel-eslint-plugin-development/package.json
+++ b/eslint/babel-eslint-plugin-development/package.json
@@ -32,5 +32,5 @@
   "bugs": {
     "url": "https://github.com/babel/babel/issues"
   },
-  "homepage": "https://github.com/babel/babel/tree/master/eslint/babel-eslint-plugin-development"
+  "homepage": "https://babeljs.io/"
 }
diff --git a/eslint/babel-eslint-plugin/package.json b/eslint/babel-eslint-plugin/package.json
index e963cee43581..8d9134a40d18 100644
--- a/eslint/babel-eslint-plugin/package.json
+++ b/eslint/babel-eslint-plugin/package.json
@@ -24,7 +24,7 @@
   "bugs": {
     "url": "https://github.com/babel/babel/issues"
   },
-  "homepage": "https://github.com/babel/babel/tree/master/eslint/babel-eslint-plugin",
+  "homepage": "https://babeljs.io/",
   "peerDependencies": {
     "@babel/eslint-parser": "0.0.0",
     "eslint": ">=6.0.0"
diff --git a/packages/babel-parser/CHANGELOG.md b/packages/babel-parser/CHANGELOG.md
index 8a43406dd600..b3840ac8d0ac 100644
--- a/packages/babel-parser/CHANGELOG.md
+++ b/packages/babel-parser/CHANGELOG.md
@@ -9,11 +9,11 @@
 > - :house:      [Internal]
 > - :nail_care:  [Polish]
 
-> Semver Policy: https://github.com/babel/babel/tree/master/packages/babel-parser#semver
+> Semver Policy: https://github.com/babel/babel/tree/main/packages/babel-parser#semver
 
 _Note: Gaps between patch versions are faulty, broken or test releases._
 
-See the [Babel Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md) for the pre-6.8.0 version Changelog.
+See the [Babel Changelog](https://github.com/babel/babel/blob/main/CHANGELOG.md) for the pre-6.8.0 version Changelog.
 
 ## 6.17.1 (2017-05-10)
 
diff --git a/packages/babel-parser/typings/babel-parser.d.ts b/packages/babel-parser/typings/babel-parser.d.ts
index 14262ab4ccc2..bd406708a8fa 100644
--- a/packages/babel-parser/typings/babel-parser.d.ts
+++ b/packages/babel-parser/typings/babel-parser.d.ts
@@ -1,5 +1,5 @@
 // Type definitions for @babel/parser
-// Project: https://github.com/babel/babel/tree/master/packages/babel-parser
+// Project: https://github.com/babel/babel/tree/main/packages/babel-parser
 // Definitions by: Troy Gerwien <https://github.com/yortus>
 //                 Marvin Hagemeister <https://github.com/marvinhagemeister>
 //                 Avi Vahl <https://github.com/AviVahl>
diff --git a/packages/babel-plugin-transform-regenerator/package.json b/packages/babel-plugin-transform-regenerator/package.json
index cca948e01979..4bf45f4ab5e9 100644
--- a/packages/babel-plugin-transform-regenerator/package.json
+++ b/packages/babel-plugin-transform-regenerator/package.json
@@ -3,7 +3,7 @@
   "author": "Ben Newman <bn@cs.stanford.edu>",
   "description": "Explode async and generator functions into a state machine.",
   "version": "7.10.1",
-  "homepage": "https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-regenerator",
+  "homepage": "https://babeljs.io/",
   "repository": {
     "type": "git",
     "url": "https://github.com/babel/babel.git",
diff --git a/packages/babel-preset-env/CONTRIBUTING.md b/packages/babel-preset-env/CONTRIBUTING.md
index 2271a8c74834..b17d1f453b73 100644
--- a/packages/babel-preset-env/CONTRIBUTING.md
+++ b/packages/babel-preset-env/CONTRIBUTING.md
@@ -2,7 +2,7 @@
 
 ## Adding a new plugin or polyfill to support (when approved in the next ECMAScript version)
 
-### Update [`plugin-features.js`](https://github.com/babel/babel/blob/master/packages/babel-compat-data/scripts/data/plugin-features.js)
+### Update [`plugin-features.js`](https://github.com/babel/babel/blob/main/packages/babel-compat-data/scripts/data/plugin-features.js)
 
 *Example:*
 
@@ -42,7 +42,7 @@ Find the corresponding module on [`core-js@2`](https://github.com/zloirock/core-
 
 `es7.object.values.js`
 
-Find required ES version in [`corejs2-built-in-features.js`](https://github.com/babel/babel/blob/master/packages/babel-preset-env/data/corejs2-built-in-features.js) and add the new feature:
+Find required ES version in [`corejs2-built-in-features.js`](https://github.com/babel/babel/blob/main/packages/babel-preset-env/data/corejs2-built-in-features.js) and add the new feature:
 
 ```js
 const es = {
@@ -51,17 +51,17 @@ const es = {
 }
 ```
 
-If you wan to transform a new built-in by `useBuiltIns: 'usage'`, add mapping to related `core-js` modules to [this file](https://github.com/babel/babel/blob/master/packages/babel-preset-env/polyfills/corejs2/built-in-definitions.js).
+If you wan to transform a new built-in by `useBuiltIns: 'usage'`, add mapping to related `core-js` modules to [this file](https://github.com/babel/babel/blob/main/packages/babel-preset-env/polyfills/corejs2/built-in-definitions.js).
 
 ### Update data for `core-js@3` polyfilling
 
-Just update the version of [`core-js-compat`](https://github.com/zloirock/core-js/tree/master/packages/core-js-compat) in dependencies.
+Just update the version of [`core-js-compat`](https://github.com/zloirock/core-js/tree/main/packages/core-js-compat) in dependencies.
 
-If you wan to transform a new built-in by `useBuiltIns: 'usage'`, add mapping to related [`core-js`](https://github.com/zloirock/core-js/tree/master/packages/core-js/modules) modules to [this file](https://github.com/babel/babel/blob/master/packages/babel-preset-env/polyfills/corejs3/built-in-definitions.js).
+If you wan to transform a new built-in by `useBuiltIns: 'usage'`, add mapping to related [`core-js`](https://github.com/zloirock/core-js/tree/main/packages/core-js/modules) modules to [this file](https://github.com/babel/babel/blob/main/packages/babel-preset-env/polyfills/corejs3/built-in-definitions.js).
 
-If you want to mark a new proposal as shipped, add it to [this list](https://github.com/babel/babel/blob/master/packages/babel-preset-env/polyfills/corejs3/shipped-proposals.js).
+If you want to mark a new proposal as shipped, add it to [this list](https://github.com/babel/babel/blob/main/packages/babel-preset-env/polyfills/corejs3/shipped-proposals.js).
 
-### Update [`plugins.json`](https://github.com/babel/babel/blob/master/packages/babel-preset-env/data/plugins.json)
+### Update [`plugins.json`](https://github.com/babel/babel/blob/main/packages/babel-preset-env/data/plugins.json)
 
 Until `compat-table` is a standalone npm module for data we are using the git commit in `packages/babel-compat-data/scripts/download-compat-table.sh`
 
@@ -72,7 +72,7 @@ So we update and then run `npm run build-data`. If there are no changes, then `p
 ## Tests
 
 ### Running tests
-See general [CONTRIBUTING.md](https://github.com/babel/babel/blob/master/CONTRIBUTING.md#running-lintingtests).
+See general [CONTRIBUTING.md](https://github.com/babel/babel/blob/main/CONTRIBUTING.md#running-lintingtests).
 
 ### Writing tests
 
@@ -80,7 +80,7 @@ See general [CONTRIBUTING.md](https://github.com/babel/babel/blob/master/CONTRIB
 
 All the tests for `@babel/preset-env` exist in the `test/fixtures` folder. The
 test setup and conventions are exactly the same as testing a Babel plugin, so
-please read our [documentation on writing tests](https://github.com/babel/babel/blob/master/CONTRIBUTING.md#babel-plugin-x).
+please read our [documentation on writing tests](https://github.com/babel/babel/blob/main/CONTRIBUTING.md#babel-plugin-x).
 
 #### Testing the `debug` option
 
diff --git a/packages/babel-runtime/package.json b/packages/babel-runtime/package.json
index f17465fd0ea8..a3cc9f76ac81 100644
--- a/packages/babel-runtime/package.json
+++ b/packages/babel-runtime/package.json
@@ -11,7 +11,7 @@
     "url": "https://github.com/babel/babel.git",
     "directory": "packages/babel-runtime"
   },
-  "homepage": "https://babeljs.io/docs/en/next/babel-runtime",
+  "homepage": "https://babeljs.io/",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "dependencies": {
     "regenerator-runtime": "^0.13.4"
diff --git a/packages/babel-standalone/package.json b/packages/babel-standalone/package.json
index a59cfc9f2e8e..a25a876a2dbe 100644
--- a/packages/babel-standalone/package.json
+++ b/packages/babel-standalone/package.json
@@ -123,7 +123,7 @@
   "bugs": {
     "url": "https://github.com/babel/babel/issues"
   },
-  "homepage": "https://github.com/babel/babel/tree/master/packages/babel-standalone",
+  "homepage": "https://babeljs.io/",
   "repository": {
     "type": "git",
     "url": "https://github.com/babel/babel.git",
diff --git a/packages/babel-traverse/src/path/family.js b/packages/babel-traverse/src/path/family.js
index b2d9cefc4e1b..e987e854fe42 100644
--- a/packages/babel-traverse/src/path/family.js
+++ b/packages/babel-traverse/src/path/family.js
@@ -209,7 +209,7 @@ export function getOuterBindingIdentifiers(duplicates?: boolean): Object {
   return t.getOuterBindingIdentifiers(this.node, duplicates);
 }
 
-// original source - https://github.com/babel/babel/blob/master/packages/babel-types/src/retrievers.js
+// original source - https://github.com/babel/babel/blob/main/packages/babel-types/src/retrievers/getBindingIdentifiers.js
 // path.getBindingIdentifiers returns nodes where the following re-implementation
 // returns paths
 export function getBindingIdentifierPaths(