This extension enhances Strava. You can show accumulated TSS on the training log.
Change log: - Fixed a critical bug: The extension doesn't work for you completely. This extension extends Strava's training log page to show weekly accumulated TSS. This is not official Strava extension but a Strava user made it to answer: https://support.strava.com/hc/en-us/community/posts/208836247-Include-weekly-accumulated-TSS-on-the-training-log