2022-10-27 update:
Doesn't seem to be working as reliably on new tabs on Firefox 106 as it used to - but I can work around it by toggling the icon off and on in the toolbar before clicking each link, which is still easier than dealing with a bunch of separate windows.

One may be able to reproduce the issue by dragging a tab to another window (which seems to cause the single window add-on to lose track of it), then try clicking a pop-up link and observe that the link opens in a new window. E.g. on webbrowsertools dot com's popup-blocker test.

2021-09-29 original review:
Invaluable when working with Fieldpoint, which wants to either show everything in multiple columns in one window (impossible to handle multiple tickets), or always pops out to a separate window when "pop out" is enabled (no built-in way to work with tabs in Fieldpoint). This Single Window extension forces the pop-outs to open in new tabs instead, and makes working with multiple tickets much more practical!

My only desire is if I could set it to only enable on certain domains. It doesn't cause much trouble, but I do have to remember to toggle it off or it interferes with the print button on eBay invoices.

Seems to work well, thanks!

Does not work on saved html links.

Doesn't work for me on Google image searches. Clicking "Visit" opens the linked page in a new tab. Yes Single window mode is enabled :(

Is there possible when the new tab opened, but not to switch to it immediately.