Telegram online conflicts with container in Firefox v137

[KromBitje]

De telegram-site telegram.org works fine in Firefox.
But I have problems with the Telegram online service (https://web.telegram.org )

• This worked fine with Firefox v136
• but it seems it is NOT working in v137.
• The Telegram online service works fine in Chrome.
• Extra info:
  • I'm using the FF-add-on 'Multi-Account containers' v8.2.0
• When I create a Tab in Firefoxv137 without a container(=default container), Telegram online works fine.
• When I create a Tab in Firefoxv137 with a container, Telegram online no longer works.
  So it seems that the Telegram online service
  it not working in Firefoxv137 when a container is selected with the 'Multi-account container' add-on !

Can anybody reproduce this situation ?