hyperlinks wont open in emails,

I'd expect hyperlinks to open in a web browser.

in Tools>options> attachments, https is set to "always ask" when I set it to "use google chrome"

Hyperlinks aren't attachments, so this approach is doomed right from the start.

See https://support.mozilla.org/kb/hyperlinks-in-messages-not-working

This problem has only occurred from the last update of Thunderbird, when I goto Tools>options> attachments, https is set to "always ask" when I set it to "use google chrome", and exit, when I go back in to check, it has gone back to "always ask" it doesn't seem to save. Previously when I clicked on a link in a email, it always opened the link.

https is set to "always ask" when I set it to "use google chrome",

Content type 'https' is not supposed to be in that list in the first place, so you should delete it.

Please follow the troubleshooting steps in the support article linked above.

When I clicked on a link in emails, a window opened, "launch application" with nothing in it, with a option to choose an application , I had to point to google chrome for it to launch, there was also an option to tick a box "remember my choice which I had not ticked before and that seemed to solve the problem