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I install an add-on to Firefox, but it doesn't appear in my add-ons manager list, and after I restart Firefox, it is gone.

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I'm trying to install 1-Click Youtube Video dDownloader, which is supposed to add a download button to Yuotube video pages. I go here:

https://addons.mozilla.org/en-US/firefox/addon/1-click-youtube-video-download/

and I click "Add to Firefox." It gives me the "Install Now" pop-up screen. I click "Install Now" and it says that Firefox needs to Restart, and it will be installed when Firefox opens again. So I click "Restart Now" and Firefox restarts. Then I go to Youtube, but no button. I check the Add-Ons Manager page, and I see that it is installed in the extensions. Then, if I go to the page and click "Add to Firefox" again, and restart again, and go to Youtube, the download button IS there, and it works perfectly. But if I quit and restart Firefox again, the download button is once again missing, but the extension is still installed. Why does this extension only work when I restart twice, and then it disappears again?

I'm trying to install 1-Click Youtube Video dDownloader, which is supposed to add a download button to Yuotube video pages. I go here: https://addons.mozilla.org/en-US/firefox/addon/1-click-youtube-video-download/ and I click "Add to Firefox." It gives me the "Install Now" pop-up screen. I click "Install Now" and it says that Firefox needs to Restart, and it will be installed when Firefox opens again. So I click "Restart Now" and Firefox restarts. Then I go to Youtube, but no button. I check the Add-Ons Manager page, and I see that it is installed in the extensions. Then, if I go to the page and click "Add to Firefox" again, and restart again, and go to Youtube, the download button IS there, and it works perfectly. But if I quit and restart Firefox again, the download button is once again missing, but the extension is still installed. Why does this extension only work when I restart twice, and then it disappears again?

選ばれた解決策

When the button does not appear, but the extension is marked as Enabled, try reloading the Youtube page bypassing the cache by pressing Command+Shift+r to see whether that triggers the extension to insert the button.

If it remains inconsistent, I would pose the question to the add-on developer from their Contact page: http://www.clickvideodownload.com/contact.php

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すべての返信 (5)

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選ばれた解決策

When the button does not appear, but the extension is marked as Enabled, try reloading the Youtube page bypassing the cache by pressing Command+Shift+r to see whether that triggers the extension to insert the button.

If it remains inconsistent, I would pose the question to the add-on developer from their Contact page: http://www.clickvideodownload.com/contact.php

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It works for me both with the Flash player and with the YouTube HTML5 player

This issue can be caused by one of the other extensions that you have installed.

Try to disable all other extensions to see if that helps.

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Thanks jscher. That does work. Do I have to do that every time I go to a youtube page? It's not a huge deal if I do, but it seems weird that I have to reload and bypass the cache every time I want the button to appear. Regardless, your method does bring the button up when I go to a youtube video page, and then hit command-shift-r to reload it, so thanks a bunch!

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Thanks for the suggestion cor-el, but unfortunately, it is the only extension I have installed at all on Firefox currently. Just installed Firefox today, specifically so I could use it to download youtube videos (Chrome seems to have severely limited their third-party add-ons).

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Hi KoalaJohnson, the combination of Firefox's aggressive caching and the change in Youtube where the page changes internally rather than loading a new address can cause problems for some add-ons. I suggest keeping an eye on it to see whether there is a pattern, and report it to the add-on developer for suggestions.