User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.3a) Gecko/20021210 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.3a) Gecko/20021210 This is a "meta" bug in the sense that it's a superset of bug 159104 and bug 184660. Each of those ask for a specific case in which a single tab should be overwritten by a tab group bookmark or by a Home page that's been set to a tab group. I believe that neither one of those goes far enough and that a single tab, regardless of its content, should always be overwritten by any tab group bookmark or Home page that's been defined as a group of tabs. The existence of a browser window with a single tab open should be an exception to the current "always append" behaviour of tab groups that was introduced way back in bug 134800. (And which is still being "questioned" by bug 153016, bug 158365, and bug 159266 - although all 3 of those would seem to not have a problem with the one specific change addressed by overwriting a single tab.) Fixing this bug would fix bug 159104 and bug 184660. Reproducible: Always Steps to Reproduce:

Note the progress on bug 203960. If it is finally resolved as FIXED, it will also fix this bug. (Currently, this bug is "fixed at the moment" because of it.)

Fixed by fix for bug 203960.

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