@volanar After upgrading to v1.18 this issue is resolved.
1.17.0 upgrade thumbnail issue
I upgraded our Dev environment to 1.17.0 this morning and any topics that had a thumbnail before the upgrade no longer display one.
The environment was upgraded from 1.16.2 to 1.17.0 and when a topic is edited the thumbnail still displays in composer but it does not display on the topics list page.
If a new topic is created it does display the thumbnail as usual though.
Our forum use-case relies on thumbnails a good deal so this is definitely a problem for us.
@julian It doesn't show up in any of those views: category, recent or unread.
@jminer Thanks, I'll take a look. I had added in backwards compatibility but seems like it isn't working 100%.
@julian I just updated to 1.17.2 and still have this issue where any topics created before the 1.17.0 upgrade don't display thumbnails.