In non-native applications, in the Open File dialog, I can see hidden files but I can't select them I have a problem with some non-native mac software (Perforce Diff and Kdiff3). 

When I use the Open File Dialog, I can see the hidden files, but I can not select them or interact with them at all.

In contrast, when using the native Mac TextEdit, when I use the Open File Dialog, I can see and open the hidden files.



This is a screenshot of the Kdiff3 Open File Dialog. I can see the hidden files, but I can not select them.





OS X version 10.10.3 Yosemite.

I did this to make Finder show hidden files

defaults write com.apple.finder AppleShowAllFiles YES


I did this to make the file open dialog show hidden files

defaults write -g AppleShowAllFiles -bool true
You can often alt/option click on files to force open them.