Approximate time tracking (based on Git logs, made because of Helsinki University requirements):
total: 224h
(grep '^    2' doc/timeusage.md|cut -c15-17|tr -d ' '|tr '\012' +;echo 0)|bc -l

2022-06-15  4h improving coverage
2022-06-14  6h improving coverage, some refactoring
2022-06-13 10h unit tests, to satisfy HY requirements
2022-06-12 14h refactoring, documentation, to satisfy HY requirements
2021-12-25  1h bugfixes
2021-10-26  1h documentation
2021-04-07  4h documentation
2021-04-06 10h optimizations
2021-04-04  7h improved SGR support, refactoring
2021-04-02 16h optimizations
2020-09-16  2h refactoring
2020-09-01  1h bugfixes
2020-07-11  2h autoinput features
2020-04-25  1h font features
2020-04-24  2h font features
2020-04-22  1h bugfixes
2020-04-21  1h bugfixes
2020-04-20  1h bugfixes
2020-04-19  3h font features
2020-04-18  6h features, bugfixes
2020-03-30  8h documentation on fonts, bugfixes
2020-03-29  4h features, improvements on font usage
2020-03-28  4h features, improvements on font usage
2020-03-28  5h documentation on fonts
2020-03-27  4h documentation on fonts
2020-03-26  6h features, new fonts
2020-03-25  7h features, new fonts
2020-02-27  1h features
2019-12-23  1h features
2019-09-08  1h bugfixes
2019-06-04  4h video recording support updates
2019-05-06  3h scrollbar render hack
2019-05-04  1h bugfixes
2019-05-01  3h documentation, bugfixes
2019-04-29  2h design / implementation, livestreamed on YouTube (part 6)
2019-04-26  3h documentation, more complete vt support
2019-04-25  2h documentation, bugfixes
2019-04-24 12h documentation, improved SGR support
2019-04-23  7h documentation
2019-04-22 11h coding (fonts and encodings)
2019-04-18  1h coding
2019-04-17  5h coding
2019-04-16  2h coding (OSC & DCS commands)
2019-04-15  1h documentation (Sixel support)
2019-04-14  4h documentation & coding
2019-04-13 10h design / implementation
2019-04-13  3h design / implementation, livestreamed on YouTube (part 5)
2019-04-11  5h design / implementation
2019-04-10  3h design / implementation, livestreamed on YouTube (part 4)
2019-04-07  3h design / implementation, livestreamed on YouTube (part 3)
2019-04-02  2h design / implementation, livestreamed on YouTube (prat 2)
2019-03-31  3h design / implementation, livestreamed on YouTube (part 1)