Console gets spammed with "not active or paused - skipping speed" messages, what are these?
There seems to be an onclose-like handler which warns me that I might have not saved the changes (I've uploaded 6 files). Do I need to "save" somehow? I see no "Save" button, nothing similar.
The warning message that you receive when trying to close the page is only there to prevent accidental exits and in case you're in the middle of an upload or if you haven't copied the URLs of the uploaded files.
Unfortunately browsers no longer allow you to change the warning message, hence why it's telling you to save.