Unable to Upload/Select Files from Copyediting Stage (fix ineffective)

Some Submissions at Copyediting Stage get stuck with a Loading… dialog (see screenshot).

This is similar to this topic and that topic.

However, I have checked that the fix covered in this GitHub issue has been applied - it has and yet the issue persists.

Like the other topics this seems to apply when some of the submission documents have been attached to discussion threads.

Please can you help as this is impacting our submitters?

We are using OJS v3.3.0.6 on PHP 7.3.32

Screenshot 2021-11-29 at 16.07.19

Here is the error_log output:

Screenshot 2021-11-29 at 18.40.09

I have submitted an extended fix in pkp/pkp-lib#7506 Unable to Upload/Select Files from Copyediting stage (fix ineffective) by p6steve · Pull Request #7507 · pkp/pkp-lib · GitHub