setting default syntax for sublime doesn't work

Question

Whenever I open a .m file the default syntax is objective-c but I want to change that to matlab. So when I open a .m file I go to

view -> syntax -> open all with current extension as..

and choose matlab. After that if I open another .m file the default syntax is matlab. But if I close sublime and open it again the default syntax is back to objective-c.

I added objective-c to ignore syntax list but now it opens .m files as plain text. Is there another way to set default syntax for a file extension?

Answer 1

In sublime3, view -> syntax -> open all with current extension as.. works if you close then open sublime.