I have been using open source software since 1999. In the beginning I paid a small monthly subscription to Mandrake Linux, but the longer I used all this free as in beer goodness I wanted to pay something back, so I tried to see if I could translate some of the programs into my mother tongue, Danish. The first projects I tried to translate was KDE and later Drupal - I did my best but the software was extremely cumbersome and bureaucratic. In the long run it was to much bother and I went back to just donating to my favourite applications, especially KDE that I have used since the beginning and still am using.
But four-five years ago I quit Facebook and made an account on Diaspora part of the federated network containing Friendica, hubzilla, and sister-application to Gnusocial/Mastodon. Here (again) the urge to be a do-good-er came over me and to my pleasant surprise I found that the translation-tools have improved immensely since the early 2000!
I have just begun translating the open-source alternative to Patreon called Liberapay (Mainly because I recently made an account), and I am also doing very slow progress in E-steem. They all use different systems, and I must say that I prefer the one used by the Diaspora developers called webtranslateit.com - but the other two are actually rather good too.