Default File Extension ignoring my preference

[milspecmonkey]

I have 3 MacBook Pros and a Studio. On all my installs, the default file extension is .cfg. All macOS running is Tahoe 26.0.1. However on my new M4 MBP I just got this week, I tried to set it up the same way as all my other devices, but this one will not work with cfg. It will show blank (no extension). Ironically, when I set it to txt it works. This is what I have in all my preference files.

{
“font_size”: 17,
“font_face”: “Jetbrains Mono”,
“highlite_line”: true,
“ignored_packages”:
[
“Vintage”,
],
“index_files”: true,
“default_extension”: “cfg”,
}

I have the .cfg set to the “open with” and “Use this application to open all documents like this one” to Sublime Text. (see attached)

I am running ST Build 4200.

macOS shows Sublime Text as the default for the .cfg

What am I missing?

Thanks

[bschaaf]

Could you clarify what isn’t working as expected, is the file not opening in Sublime Text?

[milspecmonkey]

On the OLD MacBook, I have the cfg as the default extension. It works as it should and when I save a file, it will prompt me for the name but has the .cfg at the end.

On the NEW MacBook, when I add the same preference lines including the default extension to cfg… I get no extension at all.

However, on the same NEW MacBook, if I add a txt to the preference file, it DOES show up with the .txt at the end.

Where I am trying to be at:

I have ST on my dock. I want to click it, open a file in the default file format (text on all devices) and when I am done adding the text I want, I want to hit ⌘ S and have it prompt me to save the file and have it auto add the .cfg at the end.

[bschaaf]

That’s very odd behavior, there’s nothing I can find in Sublime Text to cause that. Does it still happen after rebooting the mac?

[kingkeith]

This has been reported before:

Issue: Plain Text documents do not default to their proper file extension when saving

[bschaaf]

I don’t think it’s the same issue. They’re getting different behavior with the same setup on different computers, and they’re already using the "default_extension" setting.

[milspecmonkey]

Sadly, yes.

[milspecmonkey]

Thank you. I am going to see about both options, the plug-in and the “Plain text.sublime-settings” mehod to see if that works. If not, I will need to change my work flow to TXT instead of CFG which would be a royal pain.

[ondohotola]

I use also multiple Laptops and Desktops on Tahoe and have set up the Package Synching package (with github) but you can also use Dropbox of course. That way all are alwys in sync.