I would recommend using the Download Sound add-on. The sound is a little different than the previous default Firefox sound, but it should be the feature that you are looking for.

Other than that, I don't believe that there is any other way to get the default sound back because I believe the developers completely removed it from Firefox.

i have tried to install it, but when it looks like it finished download and verification ... installation doesn't start for some-reason ... the notification sound seems like very important feature to me, i wish you guys gave us the users the choice to enable or disable it .. :(

Sorry about that. I will try to get some information about why that feature was removed and possibly some steps on how to bring it back.

In the meantime, please feel free to share your feedback about Firefox to the developers so that they can work to make Firefox better.

• If you are running Firefox 49.0, please use this link.
• If you are running Firefox 49.0.1, please use this link.

Thanks.

I've talked with a few other members on the support forum and none of them seem to remember Firefox having a download completion sound effect.

Do you, or have you ever, had the DownThemAll! add-on installed on your browser? This add-on does make a completion noise, so it may have been what added that sound effect.

Wesley Branton said

I've talked with a few other members on the support forum and none of them seem to remember Firefox having a download completion sound effect. Do you, or have you ever, had the DownThemAll! add-on installed on your browser? This add-on does make a completion noise, so it may have been what added that sound effect.

thank you a lot Wesley Branton, i was able to download and install this add-on, it works (not as the original thing , but it's enough for me)

as for the download complete sound, i remember it being in firefox, however when i was looking for a way to enable it, i found tricks to disable it published on the net for users who find it annoying, eventually it was removed totally from firefox.

anyway, thank you for the help again, i appreciate it =)

No problem. I remember Firefox once having a sound too, but no one that I spoke with seems to remember it though and I don't remember which version removed it.

Do you have the link to the website with the tips on how to disable it by any chance?

Wesley Branton said

No problem. I remember Firefox once having a sound too, but no one that I spoke with seems to remember it though and I don't remember which version removed it. Do you have the link to the website with the tips on how to disable it by any chance?

unfortunately, i cleared my browsing data for last week , but here are some of what i remember i found :

http://askubuntu.com/questions/185708/how-to-remove-firefox-alert-sound-without-lowering-the-system-sound

https://www.youtube.com/watch?v=iNIsvrO4hzU

i remember finding a blog explaining how to disable it from "about:config" browser.download.manager.SoundAlertOnComplete .. but i can't seem to find it ...

anyway after using DownThemAll! add-on for a day i found it annoying since it doesn't start automatically and it's kind of separated from firefox ....

this is an other add on that i found useful since my problem is "not knowing" if download is complete while using other apps on my pc this makes it easier for me to check on it while using other apps on ubuntu without having switch to firefox to know if it is finished or not

https://addons.mozilla.org/en-US/firefox/addon/unityfox-revived/

hoping for the feature to appear in the future, thank you for your help

Thanks for sharing.