When using the split window plugin, when typing in the second window, pressing Ctrl-Z will undo in the original window instead of the selected second window.
Split window is a core plugin, its in the Geany repository, not the plugins repository.
But please note there are already many "split window does not work like a full second pane" so this would likely just be a duplicate.
Closed #770.
For example geany/geany#988, among many, many others. Closing as duplicate.
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