Unable to open new window

Hate to open this issue as I have no clue how to reproduce, and I currently have it fixed...for now...

Occasionally when I attempt to open MacVim, I'll get a single icon in the Dock for it (and the menu bar), but no window. It doesn't matter if I'm trying to open a blank file or passing in a file to open -- typically from an external app like Perforce/P4V. If I try to File > Open... and select a file, it will close the app down.

I tried looking in ~/Library/Logs for anything, but it doesn't look like it's writing anything there. At least not that I could find.

The only resolve I've found is to close the app, delete ~/viminfo and ~/.vimrc (or just rename to something like ~/vimrc), reopen MacVim. Then I can bring my ~/.vimrc back and things work fine again. For awhile.

I'm currently on 8.0.1420 (144), but I've encountered this on past versions as well. Usually my first step is to make sure I'm on the latest release. Let me know if there's something I should do now while it's still working to prep for the next time it happens. Or what I should look for next time it does.

Start by reviewing the reported MacVim startup and File > Open behavior, including the interaction with external apps such as P4V. Compare behavior with ~/viminfo and ~/.vimrc present versus temporarily renamed, and collect diagnostics during the next occurrence. Done would require a reproducible cause and a verified fix or clear diagnostic guidance.