In OmegaT 5.6 or later:
plugins in your user configuration folder (which you can open from OmegaT going to Options → Access configuration folder).See the plugins page for available theme plugins.
Changing colors inside the panes can be done through Preferences > Appearance > Colours.
On Mac, go to System Preferences > Language and Region > Apps, click on the [ + ] button at the bottom and add OmegaT.app to the list along with the language you want to run it in.
On Windows, find file OmegaT.l4J.ini in the installation folder and add line -Duser.language=en (using the language tag you want) at the very bottom of the file.
On the command line execute java -Duser.language=$LANG -jar path/to/OmegaT.jar (replace $LANG with the ISO 639-1 code for your desired language)
coming soon in addition to theming: better scheming.
distinction: the look&feel-theme is the window and controls, a Color Scheme is all the user definable text colors.
improvements (e.t.a.: ca. Ωᵗ v.6.2) including among others 🤩:
lets keep the planet a colorful place together ^…^
FYI: https://github.com/kosivantsov/omegat-plugin-colorthememanager
🫣 wow that looks... amazing and I had no Idea sorry maybe I should have a look around the plugin landscape before doing more tickets … i just saw an open ticket and did things that seemd necessary to the old-old interface
edit: i am pretty sure you can re-use the life-update for your plugin so the colors all over omegaT change at the same time and i imagine it will not take long for users to write scripts to cycle through colors and have a slow rainbow-effect during the day or whatever …
and i was going to rework the (at least to me) useless color preview area in the core app not knowing there was this great looking option is how i thought a color preview should be, but then on the other hand what-with the life updating and all, there is less pressing need for a good preview when the user can just view, wisiwig what i see is what i get
Last edit: st. pakebusch 2026-07-30