Try this: click view>message body as>original HTML

Hello David,

                  Not really, as normally when you click on an email to open and read it also opens Firefox whether it is already loaded or not and displays the HTML page.

I notice others are complaining of similar problems. So hopefully those workers who do so much for us can fix it. I just went back and looked at old emails and there is no url html address as the first line just the name of the company that sent it, The html address was in the 2nd line. It could be that Thunderbird is looking at the wrong line and does not know it is an html page. Wirst possibility is that emails from another server is doing something that is wrong. de Barry

Maybe if you post a screenshot of what you see, someone may offer suggestions. I am unclear on your specific issue. Thank you.

This problem appeared quite mysteriously when I fired up the computer this morning. Fortunately, David's answer above, click view>message body as>original HTML, fixed it.

It seems to me that Thunderbird looks through the email text for the first line with http/ etc to send that line

to your browser.
I can open the http page manually just by clicking on the http and openning the menu item 

"Open in your browser" and the page opens. It takes very little time but just that it is annoying. The http etc is not necessarily at the start of the line but the browser should look through ALL text. de Barry

Whoops the last line should read; --but the email program should look for ALL text for the first http.

Are you talking about the body of e-mail messages, the presentation of HTML links in messages, the presentation of senders’ addresses, or something else?

As David wrote, a screenshot would help.

Hello Rick, when you open an email and it has text, sometimes that text is just about the organisation and it is the followed by http://linkinfo Since I was last here I wrote an email and placed the http link as the first line and sent it to another address and and the link was not openned by the browse. From observing previous emails it appears that the email program is suppose to search for the first http and then send that link to the browser. The link does not have to be in the first line, it can be anywhere but the first one found is sent to the browser. Now that is what it appears to do if it works but of course that function may be disabled in my installation. If you look into your emails you will see that the first link is always the one opened. I did reinstall the Thunderbird browser but no change. de Barry

In thirty years of using e-mail, I have not heard or seen what you describe. I thought that one must always click on a link that one wants to follow.

Did you mean to mark this problem solved?

No Rick, I was unaware that I had done that. You surprise me with your remark . "I have not seen or heard of what you describe". My emails have always done that as far as I can remember. Now I understand why you could not understand my complaint. Do you use Ubuntu; Firefox; & Thunderbird. I do not think versions are the problem as that is the the combination I have used for at least ten years. Where are you Rick ? I am in Sydney.

I just went back into my archives to 2022 and the emails there also do not open now. I have subscription to a Newspaper and every night at this time I get the front page displayed just before I go to bed, I just had a look at todays and the first http is on the 7th line about 1/3 into that line. Just tried a snapshot of the screen but it now seems to have hidden the Downloads folder. It might reappear if I do restart. I will go to bed now and lookp screen capturing. Time 2345 aest. 73 de Barry ps 73 = best wishes, de = telegraph abbr for "this is".

Header of Individual messages likewise contains subitems "View">"Message body as" (within item "More".) Setting there, in the individual message, has GLOBAL effect.

Not good.