Background of the issue:
I am trying to use WP Menu Sync on my site hidden link. The content has been translated via string translation.
Symptoms:
When I run WP Menu Sync, I can select items to sync and click 'Apply Changes', but the process seems to hang with a spinner and 'Syncing menus X of XX' message that never updates.
Questions:
Is WP Menu Sync actually working when I run it?
Why does the syncing process not seem to complete or update?
Thank you for reaching out to WPML support. While one of my colleagues picks up this ticket, I’d like to provide some initial debugging steps and see if I can assist you right away.
I can see the issue based on the screenshot that you've shared. Please backup and try the basic troubleshooting steps below and see if it helps:
1. Disable all the plugins except the WPML related ones from your WordPress Dashboard > Plugins and see if the issue is gone, if so, activate one plugin at a time until the culprit one is found.
3. Temporary change to a default WordPress theme such as the ‘TwentySeventeen’ theme from your WordPress Dashboard > Appearance > Themes menu.
I further investigated, and it appears the conflict lies with WPML and ACF, particularly the ACF Multilingual plugin. If that is turned off, the WP Menu Sync works.