That would be a chrome setting, not a Thunderbird one.

thanks david. i and others have asked this question in Google Help but no one answered ☹️. i appreciate your suggestion.

I doubt there is a solution. Thunderbird simply passes the link to the operating system to open using the default browser. So there is little if anything Thunderbird knows. YOu have more control on Linux, but windows it is the operating system all the way.

Check out the registry edit in this link https://superuser.com/questions/166479/force-chrome-to-open-new-pages-in-new-window-not-tab-when-opened-from-a-progr That should work as it modifies the command line used by chrome to force a new windows for the link.

i tried the registry edit. works for a while (hours, days, ...) until some unknow process backs out the edit.

tx for the suggestion.

i tried the registry edit. works for a while (hours, days, ...) until some unknow process backs out the edit. tx for the suggestion.

ah well, perhaps look for a more capable browser then. Or try and workout why your registry is changing. Given the controls in windows against applications changing program defaults, it must be something you have authorized. I would guess chrome itself or your antivirus product of choice, or some optimization software like CCleaner