How to add new MIME-type
I use these files to keep all of my development notes in one place. In my notes I have links to various code fragments, mainly in Python. When I click on those links, Firefox opens the file in another tab and displays it as text.
I'd like to add a MIME-type to Firefox to tell it to open .py files using Sublime Text. Is there a way to do that?
Unfortunately for here is firefox End user forum that can only can help with newer version of firefox not older versions because of security problems. If your using a specific MIME you should contact the site or creator to give further assistance to using it.
If you set .py files in Windows File Explorer to open by default with Sublime Text then Firefox would offer this choice in an open with dialog. With links to local files this can be more challenging because there is no server involved that can send a file with a specific MIME (content) type. Maybe use server software and localhost.
Note that you can use the Scratchpad to take notes.