fix readme to explain that spellcheck option is activated by default …

…since Electron 9

readme.md

@@ -32,7 +32,7 @@ let mainWindow;
 
 	mainWindow = new BrowserWindow({
 		webPreferences: {
-			spellcheck: true
+			spellcheck: true // enabled by default since electron 9
 		}
 	});
 })();
@@ -68,7 +68,7 @@ let mainWindow;
 
 	mainWindow = new BrowserWindow({
 		webPreferences: {
-			spellcheck: true
+			spellcheck: true // enabled by default since electron 9
 		}
 	});
 })();
@@ -127,7 +127,7 @@ Default: `true`
 
 Show the `Learn Spelling {selection}` menu item when right-clicking text.
 
-Even if `true`, the `spellcheck` preference in browser window must still be enabled. It will also only show when right-clicking misspelled words.
+Even if `true`, the `spellcheck` preference in browser window must still be enabled on Electron 8. For Electron 9 or higher, this is done by default. The spellcheck will also only show when right-clicking misspelled words.
 
 #### showLookUpSelection
 
@@ -279,7 +279,7 @@ Even though you include an action, it will still only be shown/enabled when appr
 
 `MenuItem` labels may contain the placeholder `{selection}` which will be replaced by the currently selected text as described in [`options.labels`](#labels).
 
-To get spellchecking, “Correct Automatically”, and “Learn Spelling” in the menu, please enable the `spellcheck` preference in browser window: `new BrowserWindow({webPreferences: {spellcheck: true}})`
+To get spellchecking, “Correct Automatically”, and “Learn Spelling” in the menu, please enable the `spellcheck` preference in browser window: `new BrowserWindow({webPreferences: {spellcheck: true}})` if you are on Electron 8.
 
 The following options are ignored when `menu` is used: