Maybe I'm just missing it in the settings, but after upgrading (after 4 years), I'm starting to get complaints about how large embedded videos are -- they're taking up all available space, which is way too large (at least on my forums, they're even larger than below).
Is there a setting somewhere to specify max width?
GangsterBB.NET (Ver. 7.6.1.1) PHP Version 5.6.40 / MySQL 5.7.23-23 (was 5.6.41-84.1) / Apache 2.4.54 2007 Content Rulez Contest - Hon Mention UBB.classic 6.7.2 - RIP
Make sure that when you upgraded from v7.5 to v7.6 that you installed the new themes and media tags (such as youtube); simply use the import function (in the style editor and the media tag editor) and import the data in the /install/custom_codes and /install/styles folders. I think that you should just be able to add a max-width: 500px; on the .video-container class (in common.css) which should limit how large your video can be.
We overhauled just about every faucet of UBB.threads for the v7.6 line, and a good portion of these updates affect mobile capability and standardization.