Thread:Project:Support desk/No default image caption since update to mediawiki 1.16.4

Since i updated to mediawiki 1.16.4 whenever i insert a image no default caption (or tooltip)is added anymore. Normally the filename was added as caption.

I even can reproduce this in this wiki version (guess 1.17.x)

No Image caption (aka tooltip)

I guess some default has changed, but i can't find anything pointing me into the right direction