How do I configure editor used by Log / Open Selected Version?

[Jane Eisenstein]

When I select Open Selected Version on an html file, the file opens in my default browser. How do I configure SourceTree to open html files in a text editor?

[Seth]

I believe it just uses your operating system's program association for that file.

[Something Something]

Seth's comment is correct, it uses the OS default.

But a more complete answer is you can also customize the default behavior for non-default editors through Tools > Options > Custom Actions. In theory at least, because with v1.9.10.0 it doesn't work too well because my editor remains in the background. But that's better than nothing, if you can't change the system default (can be inconvenient for HTML, for example). In my experience you have to restart SourceTree for this to take effect, by the way (the program doesn't inform you of that, which made me waste time on pointless "troubleshooting").