I can see there is a way to expand all groups, and then a way to undo the expansion. However, I don't see any way to collapse all groups, which would be useful.
collapse all closed (i.e. with no windows open) nodes would also be good
It's been 7 years.... It would be REALLY NICE IF WE HAD THIS DECENTLY-BASIC FEATURE BY NOW!
Yeah seriously we really need this. Its pretty easy to end up with a long backlog of crashed windows and then have to sit there for like a half hour clicking the collapse button before you can even start clicking the "x" to delete the windows.
Open Tab outliner window
Press F12 to bring up developer console
Click the console tab and copy and paste the code below and hit enter
Found this on github, and can confirm it works.
treeView.treeModel.currentSession_rootNode.subnodes.forEach(node => node.setCollapsing(true))
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