MacVim doesn't open a window (except from Terminal, and then only one window)

[Paul S. R. Chisholm]

If I start MacVim from the dock, it launches, but it doesn't have an open window. File / New Window and File / New Clean Window are grayed out (and of course don't do anything).

If I start MacVim from the command line, e.g.:

$ /Applications/MacVim.app/Contents/bin/gvim

then a window opens. The "new window" menu items are still grayed out. Running that command line again opens a second window.

It happens when installed with "brew install --cask macvim" or from macvim.org.

Versions of stuff:

• VIM - Vi IMproved 9.1 (2024 Jan 02, compiled Jan 4 2024 03:08:50) / macOS version - arm64 (from macvim.org)
• M2 MacBook Air running macOS Sonoma 14.2.1
• no .vimrc file
• shell: GNU bash, version 5.2.26(1)-release (from Homebrew)