Your comments

UPDATE to yesterday's experience because it started working again. 

Here are the exact order of events, in case it's somehow related to the attachments of additional peripheral devices / monitors (e.g., second screen issue mentioned earlier):

  1. TO was working while using laptop (Mac) docked (connected to a hub that connects to a monitor, etc.)
  2. TO was working while using laptop DISconnected from any peripherals
  3. Applied system update and restarted laptop (multiple times) - after which TO would NOT work as usual - no windows opened (even 'out of view') when a node was double-clicked.
  4. Put laptop to Sleep
  5. Connected laptop to dock again & woke up from sleep - Works as usual!

Having this issue again today after an operating system update on my Mac. Have rebooted several times to no avail. Opened Chrome Extensions and turned this TO extension off and then back on- that doesn't help.

What I noticed that may be key to troubleshooting (and I believe is mentioned by someone else in a similar thread): When I create NEW Windows and tabs those work as expected - they can be closed and re-opened in the TO window by double-clicking on one.

All my hundreds of "old" tabs/nodes in the TO tree (from this morning's session) can NOT be opened by double-clicking on them. 

HTH to correct this super-annoying problem.

I was just about to re-purchase TO for my Google Account at work when this started. :(

Mine mysteriously started working fine again today 

Mac-Chrome: Version 102.0.5005.115 (Official Build) (arm64)

I don't believe anything changed, other than I put the computer to sleep for a few days.

@Sridhar thanks for workaround but keyboard shortcuts don't work in the free version (and my paid version is in another google account :(  )