I've currently got three versions of IntelliJ on my Mac
I am having a hard time changing the default. If i do a Get Info
I can change an individual file to open with version 9
But if I do a Change All from here, suddenly it reverts back to 8.1.4! I Googled on this and some people threw out a red-herring of changing the padlock at the bottom prior to doing the change all, but it had no effect. From Googling I also know you are supposed to be able to achieve this by another means. But this failed for me too. i.e.
But when I look at another .ipr file in another folder, it still opens with 8.1.4 and the Open With dialog still has 8.1.4 as the default! Any ideas?