I have a custom dc:format for a video : video/vnd.xxxx.brightcove. And i have a custom video dam asseteditor for this created under "/apps/dam/content/asseteditors/video/vnd/tvnz/brightcove/" to override "/libs/dam/content/asseteditors/video". In damadmin's search tab, if i search for videos and from the result of videos returned, when i click to open the video, it opens in the default asseteditor and the left panel shows no 'Type' info. (although dc:format property is available on the asset metadata). Here's the wierdness -> when you now refresh this page, it re-loads in the custom video dam asseteditor. There is a workaround for this - if you ensure that the video asset has a property "dam:MIMEtype", it opens in the correct video dam asseteditor everytime and it shows the 'Type' correctly to be 'video/vnd.xxxx.brightcove' in the left pane.
This looks like a bug in CQ. As long as dc:format is available, this should be used to deduce the dam:MIMEtype and use the appropriate asseteditor. Has anyone experienced something similar?