Tabs outliner unresponsive and crash?

I installed Tabs Outliner a couple of years ago and it saved me many times by helping me restore my tabs after my chrome crashed. Yesterday my chrome crashed again and I tried to open Tabs Outliner but it kept saying "page unresponsive" and crashed a few times, until hours later it finally responded and the tree showed up, but then when I clicked on the last crashed tree and tried to restore the tabs, it was chrome's turn to be unresponsive.

I wonder if there is a fix to this. Is it because I had too many tabs (300 ish) open and my chrome crashed quite a few times so the data size in Tabs outliner was too big? Is there a way to delete the old crashed trees and only keep the most recent one? Or should I remove Tabs outliner from chrome and reinstall it?

Also I had my chrome tabs in groups. Is there a way for tabs outliner to save the group settings instead of just save the individual tabs?

Thanks! Any advice appreciated.

Sophie