Ignore this one. I found a setting in about:config that was set wrong and links now open correctly. To open a new bookmark in the same window I still have to use the Context Menu "Open" option, an extra click, but I can live with it.

Bookmarks and Tabs

Left-clicking a bookmark normally does open it in the same tab (unless you hold down the Ctrl key to direct it to a new tab, or the Shift key to direct it to a new window). There is a setting to switch that, so you could check whether it got switched:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste tabs and pause while the list is filtered

(3) If the browser.tabs.loadBookmarksInTabs preference is bolded and "modified" or "user set" to true, double-click it to restore the default value of false

Does that explain it?

Links and Tabs

By default, Firefox intercepts links that sites send to a new window and opens them in a new tab instead. Sites do that in two ways:

• Setting a target attribute on the link, such as target="_blank"
• Using the script method window.open(), which creates a popup window

There is a built-in setting to override this and force all links to open in the same tab. You can still open a regular link in a new tab or window when you want to using the right-click context menu items. (As far as I know, you can't do that reliably with scripted links.)

I don't use this setting, so let me know how it works out for you:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste neww and pause while the list is filtered

(3) Adjust the preferences as follows:

(A) browser.link.open_newwindow - for links in Firefox tabs

• 3 = divert new window to a new tab (default)
• 2 = allow link to open a new window
• 1 = force new window into same tab <= Try this one

(B) browser.link.open_newwindow.restriction - for links in Firefox tabs

• 0 = apply the setting under (A) to ALL new windows (even script windows) <= Try this one
• 2 = apply the setting under (A) to normal windows, but NOT to script windows with features (default)
• 1 = override the setting under (A) and always use new windows

(C) browser.link.open_newwindow.override.external - for links in other programs

• -1 = apply the setting under (A) to external links (default)
• 3 = open external links in a new tab in the last active window <= Try this one
• 2 = open external links in a new window
• 1 = open external links in the last active tab replacing the current page

To return to normal if things go haywire, right-click each "modified" preference and choose Reset.

If you need a test page: https://jeffersonscher.com/res/popit.html