"The list of languages in the New Target Language combo is extremely short"
The list shows the langauges who are almost translated. When you translate an new language - every language can be translated - then this language (who is in the languages directory) will be added to the list.
"Max, the precompiled binaries, Linux version, depends on GTK2. As newer Linux distros (such as Ubuntu) no longer ship with gtk2, that seems an issue. So I looked for the project source and found what looks like a dependency on firebird ??"
GTK2 is now the standard in Lazarus 4.8. Lazarus 4.8 is not full ready for use with GTK3. When Lazarus 5.0 with GTK3 is ready then I will make a GTK3 Version.
I am working on Linux Mint 22.3 and MyLangEdit3 runs very good. What's the problem then on this time with GTK2?
And it run an Windows 11 without any problem, too.
Firebird Embedded is used for save translations in database. That makes translations very comfortable because all your ready translations you can insert in a new program. And you can take translations from a existing PO-File in database. This translations you can use for every program you need a translation. Every found translation from Google Translate you can (eventually edited) save automatically in database . You must not install Firebird (because is embedded) and nothing is to do more as start the program.
All of you two have not tested the program really. But you post negative comments. I think this is not the way Lazarus should be forced for a good future.