default actions http/s not working unless use open in Browser as a link..

I used to be able to 'click' an email link,.. and the page would auto open in chrome,.. with a message at the top of the screen informing me this was happening. For some reason I must now use right button, and open in browser,.. in order to open the email link provided. s/w as follows:- Name Thunderbird Version 156.0 Build ID 20260915113124 Distribution ID ubuntu-snap-build User Agent Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:156.0) Gecko/20100101 Thunderbird/156.0 OS Linux 7.0.0-34-generic #34-Ubuntu SMP PREEMPT_DYNAMIC Wed Sep 2 14:29:37 UTC 2026 OS Theme Yaru-yellow / Adwaita Application Binary /snap/thunderbird/1259/usr/lib/thunderbird/thunderbird-bin I have tried deleting the handler.json file but this does not fix or resolve the issue. My current Files & Attachments,.. has just a pdf entry,... set to preview in Thunderbird,.. and this duly open pdf's in a TB tab. I have found the config editor settings,... for network.protocol-handler.external.http and network.protocol-handler.external.https and can verify they are set to true But I still cannot just click on an email link,.. and have it open in my default browser.... Can anyone offer some options as to what i am doing looking where,.. wrong. Many Tx