I changed my firefox profile name from abc to xyz Before: firefox -profile abc with search engine as DuckDuckGo. Now: firefox -profile xyz and the default search engine is now Google, even though all the other settings I set are the same.

is it reproducible?

Yes.

Are you using FF40.0.3?

I tried with FF40 on WIn 7, I can't reproduce it. COuld you create a new profile and test your STR.

I am using 40.0.3 on Windows 7 as well. I created a new profile abc using firefox -profile abc, set the default search engine to DuckDuckGo, closed Firefox, renamed the profile to xyz, opened Firefox with firefox -profile xyz, and the default search engine is now Google.

I retried: firefox.exe -p > new profile "abc" > changed GG for DDG > closed FF > firefox.exe -p > renamed "abc" to "xyz" > result: search engine is DDG Maybe you have something from Google installed on your OS that's hijacking the search engine. That's a common issue.

(In reply to Loic from comment #6) > I retried: > firefox.exe -p > new profile "abc" > changed GG for DDG > closed FF > > firefox.exe -p > renamed "abc" to "xyz" > result: search engine is DDG firefox.exe -p Profile Manager --------------- Create Profile... abc Rename Profile... xyz The same thing happened for me as well, however when I say renamed the profile I do not mean using the Profile Manager. Open Command Prompt. C:\Users\User>"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -profile abc This will create a new profile at C:\Users\User called abc, this is unlike the Profile Manager which creates a profile in %appdata% and prefixes it with a random string, and a dot, and then the name. Change the default search engine to DuckDuckGo. Close Firefox. rename abc to xyz C:\Users\User>"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -profile xyz The default search engine is now Google.

(In reply to charlie from comment #7) > rename abc to xyz To be sure, you mean renaming the profile name by editing manually the folder name?

Yes, after opening the Command Prompt, and executing C:\Users\User>"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -profile abc there should be a folder called abc in C:\Users\User. After changing the default search engine, and closing Firefox, I then renamed this from abc to xyz using Windows Explorer.

Regression range: http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=7f81be7db528&tochange=6cbdd4d523a7 Florian Quèze — Bug 1029148 - store current search engine configuration outside of prefs, r=MattN.

This is on purpose, to make it difficult for search hijackers to change a user's default engine by just dropping a file in the user's profile folder.

(In reply to Florian Quèze [:florian] [:flo] from comment #11) > This is on purpose, to make it difficult for search hijackers to change a > user's default engine by just dropping a file in the user's profile folder. DuckDuckGo is an in-built search engine found at chrome://browser/locale/searchplugins/, why should it revert to Google.

(In reply to charlie from comment #12) > (In reply to Florian Quèze [:florian] [:flo] from comment #11) > > This is on purpose, to make it difficult for search hijackers to change a > > user's default engine by just dropping a file in the user's profile folder. > > DuckDuckGo is an in-built search engine found at > chrome://browser/locale/searchplugins/, why should it revert to Google. We could maybe add an exception for engines that are part of omni.ja. Is there a real use case that makes this worth fixing? You don't rename your profile folder everyday, do you?

I copy my Firefox profile to different computers I use, and sometimes I make a copy of the profile, in the same folder (meaning I have to give it a different name), for opening different email accounts with the same provider in Firefox. Copying the profile (and keeping the name of it the same) to another folder does not change the default search engine, however renaming it does.

You can use Sync for that. And use the private browsing mode to open several tabs with the same webmail provider.

(In reply to Loic from comment #15) > You can use Sync for that. It is easier for me to copy a folder than log into Sync. > And use the private browsing mode to open several tabs with the same webmail provider. I use the 'Saved Passwords' feature within Firefox (Password manager) to remember my passwords and this feature does not work in Private Browsing Mode.

It's in the hands of devs now, not mine.

(In reply to Florian Quèze [:florian] [:flo] from comment #13) > (In reply to charlie from comment #12) > > (In reply to Florian Quèze [:florian] [:flo] from comment #11) > > > This is on purpose, to make it difficult for search hijackers to change a > > > user's default engine by just dropping a file in the user's profile folder. > > > > DuckDuckGo is an in-built search engine found at > > chrome://browser/locale/searchplugins/, why should it revert to Google. > > We could maybe add an exception for engines that are part of omni.ja. Is > there a real use case that makes this worth fixing? You don't rename your > profile folder everyday, do you? Could there be a pop-out warning out of the search bar (or something) if Firefox reverted the search engine back to Google; if Firefox reverted the search engine back, then this indicates that something irregular has occurred, and would it not be a good idea to inform the user of this?

(In reply to charlie from comment #18) > Could there be a pop-out warning out of the search bar (or something) if > Firefox reverted the search engine back to Google; if Firefox reverted the > search engine back, then this indicates that something irregular has > occurred, and would it not be a good idea to inform the user of this? A pop-out, no. But we are planning an interstitial page for other cases where we would like to revert the search engine with the user's permission (see bug 1203168). I'll keep the case discussed here in mind, and if I can improve the situation for this case without complicating the code, I may do it.