Interesting read. I wonder where OP got the specs for the device itself, i.E. what it expects in terms of data and what the response (interrupt) values mean?

They also offer Threema Libre on F-Droid for all us folks who degoogled their phone

Quality movie, i can second the recommendation

There is at least one exception in my opinion where this is acceptable: when writing special characters with diacritics etc. (for example é, à), caps-lock can help capitalizing these letters since they often already require shift to be pressed. I’m aware that there are other ways (i.E. type the diacritic first, then the letter), but the caps-lock way seems easier to me.