Make WordPress Core

Opened 14 months ago

Last modified 4 weeks ago

#46110 assigned defect (bug)

IE11: JS "Syntax error" related to wp-polyfill-formdata

Reported by: afercia Owned by: atimmer
Milestone: 5.5 Priority: normal
Severity: normal Version: 5.0
Component: Build/Test Tools Keywords: has-screenshots has-patch
Focuses: javascript Cc:


In Internet Explorer 11, there's a JavaScript "Syntax error" related to wp-polyfill-formdata. The error happens in various pages, e.g. in edit.php and post.php.


IE11 doesn't support "arrow functions" and other ES6 features in that file. Asked for feedback on Slack #core-editor and it was pointed out that seems core is using the wrong file from the package.

Wrong version used in core:


Correct version used in the Gutenberg plugin:


Introduced in [43719] /Cc @omarreiss @atimmer

Attachments (1)

46110.diff (606 bytes) - added by mariyan96 5 months ago.

Download all attachments as: .zip

Change History (16)

#1 @ocean90
14 months ago

  • Component changed from General to Build/Test Tools
  • Keywords needs-patch added
  • Milestone changed from Awaiting Review to 5.1.1

The file is only loaded if SCRIPT_DEBUG is set.

We could ask the author to include a formdata.js in a /dist directory. They are using the Closure Compiler so the WHITESPACE_ONLY option would fit for this.

#2 @atimmer
14 months ago

I've asked the author of the library to include a non-minified build file: https://github.com/jimmywarting/FormData/issues/69.

I see two possible workarounds:

  • Build the file ourselves in the webpack configuration.
  • Ship the minified file as the non-minified file.

The second one is easier to implement, the first one is better.

#3 @netweb
13 months ago

  • Owner set to atimmer
  • Status changed from new to assigned

This ticket was mentioned in Slack in #core by lukecarbis. View the logs.

13 months ago

#5 @lukecarbis
13 months ago

  • Milestone changed from 5.1.1 to 5.2

#6 @jorbin
12 months ago

  • Milestone changed from 5.2 to 5.3

Bumping due to lack of activity upstream.

#7 @afercia
10 months ago

Noting the upstream issue on GitHub has been automatically closed by the "stale bot" because of lack of activity and seems the project maintainers aren't inclined to ship a non-minified version.

This ticket was mentioned in Slack in #core by david.baumwald. View the logs.

6 months ago

#9 @netweb
6 months ago

  • Milestone changed from 5.3 to 5.4

Due to lack of updates, punting this to 5.4 to clear the way for 5.3

5 months ago

#10 @mariyan96
5 months ago

  • Keywords has-patch added; needs-patch removed

Hey guys,

We were on WordPress Contributors Day (Sofia, Bulgaria) and this is my first ticket.

The changes consist of loading the minified assets which are going through Grunt. This should solve a lot of other compatibility issues as well. Attaching 46110.diff​ file with my changes.

#11 @aduth
7 weeks ago

Noting that the patch provided for #49423 may incidentally resolve this.

This ticket was mentioned in Slack in #core by mike. View the logs.

5 weeks ago

This ticket was mentioned in Slack in #core by david.baumwald. View the logs.

4 weeks ago

#14 @aduth
4 weeks ago

46110.diff may work, but only because it bypasses SCRIPT_DEBUG to force the minified script of all vendor scripts to always be loaded. While this resolves the issue of this ticket, in doing so it breaks expectations that SCRIPT_DEBUG load unminified files.

Related: https://wordpress.org/support/article/debugging-in-wordpress/#script_debug

#15 @jorgefilipecosta
4 weeks ago

  • Milestone changed from 5.4 to 5.5
Note: See TracTickets for help on using tickets.