Original message disappears when replying, forwarding, or editing a draft

[mrdmswit]

Hello,
First, thank you for this add-on, which is very useful to me.

I am experiencing an issue when replying, forwarding, or editing a message that uses HTML. As soon as the automatic signature appears (for example, when replying), the content of the original message disappears, leaving only the line:
"On 04/09/2025 at 08:59, XXXXXXXX wrote:"

Could this be a configuration problem? I have been using Signature Switch for a few months, and I don’t recall having encountered this issue before.

Thank you,
DMSW

[4ch1m]

Did you activate this option?

[mrdmswit]

No, but I enabled it afterwards to see if it would fix my problem. But no, with this option as well, I still have the same issue.

[4ch1m]

My guess is, that you have a set up your signatures both via Thunderbird's built-in options and using Signature Switch.
That may cause interference/unwanted behaviour.

[mrdmswit]

Hello,
Thank you for taking my request into account.
No, everything is unchecked regarding Thunderbird’s built-in signature management.
To move forward with the issue I have observed on all workstations in my company: if we do not enable automatic signatures via the Signature Switch add-on, the original message or the draft editing is not altered. However, as soon as we enable the signature, it seems that its insertion purges the HTML code: some senders’ signatures disappear, as well as the content of their message.
I hope this information helps. Thanks