Hi Samuel,
It's Valerio Mazzeo here, author of GitLab Control.
Thanks for get in touch about this issue.
In a nutshell:
The GitLab Team refused to consolidated all the MIME Type for the
repository files, so I had to add exceptions for those that could be
displayed as normal text, but whose MIME Type is not text/xxx.
In this specific case the Gitlab API returns application/x-tcl for tcl files.
Thanks to your report I have just fixed this and you should be able to
browse .tcl files in the next release.
Thanks for downloading the app, I hope you are having an amazing user
experience.
Cheers,
-GitLabControl
{"html5":"htmlmixed","css":"css","javascript":"javascript","php":"php","python":"python","ruby":"ruby","lua":"text\/x-lua","bash":"text\/x-sh","go":"text\/x-go","c":"text\/x-csrc","cpp":"text\/x-c++src","diff":"diff","latex":"stex","sql":"mysql","xml":"xml","c_loadrunner":"text\/x-csrc","c_mac":"text\/x-csrc","coffeescript":"text\/x-coffeescript","csharp":"text\/x-csharp","ecmascript":"javascript","groovy":"text\/x-groovy","haskell":"text\/x-haskell","html4strict":"htmlmixed","java":"text\/x-java","java5":"text\/x-java","jquery":"javascript","mysql":"mysql","pascal":"text\/x-pascal","perl":"perl","perl6":"perl","plsql":"plsql","properties":"text\/x-properties","scheme":"text\/x-scheme","vb":"text\/vbscript","vbnet":"text\/vbscript","verilog":"text\/x-verilog","yaml":"text\/x-yaml"}