Interesting I'm accessing this forum on my home computer at the moment and still have the old layout format. I probably will not want to clear the cache information stored on my computer for a while

The change was yesterday or so

The device I was using at work, I was away from the office about two months. Seems that the new forum format has been changed since then

If you force refreshing the cache, you should have the new look also on the other computer (strange, I though I checked that before asking him :D)
Possibly still some small issues, but these will be fixed in the next days.

Where you see that other style, I assume that you are not connected/logged in?
That is the new theme of the forum, which has the advantage of being mobile-friendly, but I don't know how to apply it to existing accounts I'll ask to the forum owner.

I have access to this site from work and found this layout format like this

Discussion about images submission split to a new thread: https://imcdb.opencommunity.be/forum_topic-9967-93534-Submitting_images.html#p93534

Minor update, following a request received, now in the page that appears when one uploads a picture for comments you can simply press the Enter key to copy that URL to clipboard (in addition to Ctrl+C or the "Copy" button at is side).

I suspect issues with some ads (I really should change the ad company), even if not optimized on mobile it should work fine, as it is rather basic pages.
This site is a relic from the 2000-2010s internet It was a little tweaked to make it more usable on mobile, but it is not a mobile-first site like most of the sites nowadays.

Just wanted to chime in and say that the mobile site is very unoptimized on Safari on iOS. Sometimes I can't click on links or even the text box if I need to edit a comment.