The about:config setting aren't synced between browsers, unfortunately. Whatever you're adjusting on one you'll have to do for the others manually.

Thanks for the info. The setting I had to change was, clicking on links would stay in current tab. Maybe this should be in the settings area. Putting this option in the settings would have helped me. Maybe it can help others also.

What strange and complicated thing did you change??

** Disclaimer: The following is my understanding, but I have not tested it myself. **

I would say "it depends."

Many standard preferences that have corresponding settings in the user interface (for example, the Options page) should sync if Preference sync'ing is enabled. To see which ones are set to sync, try this:

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

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

The ones that have a value of true will sync. For example:

If

services.sync.prefs.sync.browser.startup.homepage

is true, the value of

browser.startup.homepage

should sync.

Let's say you need to have a different homepage in different installations of Firefox. In that case, you can double-click the services.sync.prefs.sync.browser.startup.homepage preference to switch it to false so the browser.startup.homepage preference does not sync.

Make sense?

Unfortunately, I don't think you can create new

services.sync.prefs.sync.whatever

preferences to sync whatever you like. Firefox probably will ignore those.