VirusTotal shows backend as malicious
Three security vendors used in Google's VirusTotal show timimi-2-1-1-Windows-Chrome-Chromium-Opera.exe to be potentially malicious.
It would probably be worth the time to contact these vendors and find out why, and to have the backend installer whitelisted.
Contacting VirusTotal for help on this is easy. Go to this support page and set the subject to "My site/file has been improperly flagged as harmful (false positive)". Fill in the rest of the information and you'll hear back from them fairly quickly.
I am also getting a virus warning on the windows/firefox one. It passes the Windows Defender check on my home machine, but my work machine throws a fit. I don't know what back-end they use for the checks.
We had a detailed discussion about this in Google groups. Please see https://groups.google.com/g/tiddlywiki/c/zHsF3YxFM8A/m/BWItsb29AAAJ