diff --git a/packages/@uppy/core/src/index.js b/packages/@uppy/core/src/index.js
index 21524b0504..67a54177fd 100644
--- a/packages/@uppy/core/src/index.js
+++ b/packages/@uppy/core/src/index.js
@@ -184,6 +184,8 @@ class Uppy {
     //    [Practical Check] Firefox, try to upload a big file for a prolonged period of time. Laptop will start to heat up.
     this.calculateProgress = throttle(this.calculateProgress.bind(this), 500, { leading: true, trailing: true })
 
+    this.validateRestrictions = this.validateRestrictions.bind(this)
+
     this.store = this.opts.store
     this.setState({
       plugins: {},