Question Cannot add attachments to posts

Because I can't really wait for anyone to agree that there's a problem, I'm moving forward.

I created a new site, and performed a fresh install of 5.0.3 on the same server so I can compare the contents of the 5.0.3 upgraded extension vs the 5.0.3 installed extension. Using diff --brief -Nr dir1 dir2, I'm comparing components/com_kunena, administrator/components/com_kunena, plugins/kunena, media/kunena. Differences will be noted here and further investigated.

components/com_kunena:
diff --brief -Nr components/com_kunena/ /arbuilders/components/com_kunena/
components/com_kunena/template/crypsis/config/params.ini differ
components/com_kunena/template/crypsisb3/layouts/widget/login/logout/default.php differ
components/com_kunena/views/announcement/view.html.php differ
components/com_kunena/views/credits/view.html.php differ
components/com_kunena/views/home/view.html.php differ
components/com_kunena/views/misc/view.html.php differ
components/com_kunena/views/search/view.html.php differ
components/com_kunena/views/statistics/view.html.php differ
components/com_kunena/views/user/view.html.php differ

That's eye-opening. Out of 14,790 files - there are 9 files that differ between the upgraded site and the freshly installed site....and this is just the components/com_kunena folder

Upon closer inspection, most of these files do not exist in the fresh install, the one that does exist is components/com_kunena/template/crypsisb3/layouts/widget/login/logout/default.php, and that has a difference of:
115c115
< <?php echo KunenaIcons::email();?>
---
> <?php echo KunenaIcons::mail();?>

Needless to say, as I move along through all of the installed kunena folders - I'm finding a lot of missing files and a few differences.

Something in your upgrade process is severely lacking. Leaving orphaned files, and leaving some files unchanged after upgrade leaves a lot to be desired.

I'll update when I find the offending files.

OK, more inconsistencies. Comparing table structure between a fresh install and my upgraded 5.0.3 - all of the upgraded tables are MyISAM, while the fresh installs are InnoDB. Many many many columns have been redefined - mostly between TINYTEXT, MEDIUMTEXT, and TEXT. There are a few VARCHAR lengths that have changed from 255 to 190. I'm also taking the opportunity to update the collation to match the fresh install.

So the DB upgrade queries don't contain queries to alter tables to match a fresh install.

These plugins caused it. Disabled and the problem went away.

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