You can use Thunderbird Write composing window to create a new signature and save as html file.

• Click on 'Write'
• Clear everything.
• Create new signature.

Note: you must select all the formatting requirements. It does not matter what is set as default, you must reselect font, font size, table, image, link etc etc using the 'Formatting Bar' to hardcode all the formatting into that signature, otherwise it will appear greyed out.

• File > Save as > File
• Save file as HTML file type in suitable location.

I have several signatures saved in a desktop folder called 'TB Signatures'.

I then use an addon extension called 'Signature Switch', so I can swap the signature to another.

Download and install the addon.

• https://addons.thunderbird.net/en-US/thunderbird/addon/signature-switch/
• https://support.mozilla.org/en-US/kb/thunderbird-add-ons-frequently-asked-questions#w_how-do-i-install-an-add-on

After installing and restarting Thunderbird:

• Menu icon > 'Addons' > 'Extensions'
• Locate 'Signature Switch' and click on 'Options'.
• add the signature html files.
• click on 'OK' when finished.

You can add the Signature Switch button to the 'Write' window Composition toolbar. See image below.

Unfortunately this does not solve the problem. Maybe I wasn't very clear with my question.

In our company works over 70 people each of them have their personal email and they have to have standart signature but with their unique name, surname, number and etc. However the style of the signature should be same for all.

In other words. Is it possible to edit each of these signatures without these employees needing to do anything or as little as possible?

Each person should do their own and save the modified html file in a suitable folder on their desktop.

If the original signature was created and saved as HTML file:

• click on 'Write'

The auto signature will probably appear.

• If there is a signature delimiter: Clear the delimiter which looks like --
• Edit email address.
• File > Save as > File
• Save file as HTML file type in suitable location.

Then make sure the account is using that signature html file.

• right click on mail account name in Folder Pane and select 'Settings'
• select 'Attach the signature from a file instead (text, HTML, or image)'
• click on 'Choose' button and locate the saved html file
• select html file and click on 'Open'
• click on 'OK'

Well I know this way but was thinking that there is faster way of doing it but I guess not. Well either way thank you for your response! At least I now know that there are no other way.