There are quite a few suggestions already concerning this, but none 100% like this:
I installed a new syntax definition via the described process. It theoretically works, however I cannot open any file of that type, even though described in the .tmLanguage file. For this reason Kodex has a switch to open any extension, something Textastic is unable to do. This is really frustrating. I hope both those features (extension from language file, all extensions possible) get implemented. Otherwise custom language syntax is pretty useless.
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