Roughly what percentage of the software you use daily is free (as in freedom)/open-source?
Almost all of it
I don't play games really often so they wouldn't count as daily use, so I guess what remains is the various firmwares on the devices (not operating systems, just firmwares), some services like DuckDuckGo, Slack, Mailbox.org, etc., and on the phone, I run LineageOS with microG but half of the phone apps are proprietary. So maybe 80%?
idk, probably more than 50%
freemdom
Maybe 50%? The stuff I use at work is proprietary but most of the software I use at home is open source
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