Ok, update is out.
Disable the “Embed YouTube Videos” option in the General section of settings to stop it embedding by default. And you can now right click to the left or right of video items (so we don’t disable the useful menu on the video itself) to show them as text.
Jeff If you really want to delete the cookies and storage, that’s in
~/Library/Application Support/Legend on Mac and
C:\Users\<you>\AppData\Local\Legend on Windows. You can delete the whole folder (except backups and docs folders if you want to keep those), but that will reset the app so you’ll have to login again. And be sure you’re online and any offline changes are synced before doing that…