Document bug with disabled inputs caused by Firefox 64 and older

README.md

@@ -44,6 +44,8 @@ You can choose between:
 - inputmask.dependencyLib.jqlite
 - .... (others are welcome)
 
+**Warning**: Using any dependency library that relies on the `CustomEvent` object or the `document.createEvent` DOM API will have issues with updating values in disabled inputs, in Firefox 64 and older. This is caused by [an old Firefox bug](https://bugzilla.mozilla.org/show_bug.cgi?id=329509), that has been fixed in Firefox 65. Currently, this means that `inputmask.dependencyLib` and `inputmask.dependencyLib.jqlite` are affected by this bug.
+
 ### Classic web with <script\> tag
 Include the js-files which you can find in the `dist` folder.