Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Mozilla サポートの検索

サポート詐欺に注意してください。 私たちはあなたに通話やショートメッセージの送信、個人情報の共有を求めることはありません。疑わしい行為を見つけたら「迷惑行為を報告」からご報告ください。

詳しく学ぶ

このスレッドはアーカイブに保管されました。 必要であれば新たに質問してください。

.mov files no longer display in FireFox on my MacBook

I have a website I developed which uses Quicktime .mov movies and that is local on my MacBook Air. I have been using Firefox without problems in the past; however, version 52.0.2 will not display the movie. The web page opens, but it's totally blank. I'd appreciate any suggestions for how to solve this problem.

I have a website I developed which uses Quicktime .mov movies and that is local on my MacBook Air. I have been using Firefox without problems in the past; however, version 52.0.2 will not display the movie. The web page opens, but it's totally blank. I'd appreciate any suggestions for how to solve this problem.

すべての返信 (2)

Could be a problem with sandboxing.

  • Bug 1321724 - [e10s] Local HTML cannot be opened in Firefox 50

Please do not comment in bug reports
https://bugzilla.mozilla.org/page.cgi?id=etiquette.html

You can disable multi-process windows in Firefox by setting these prefs to false on the about:config page.

  • browser.tabs.remote.autostart = false
  • browser.tabs.remote.autostart.2 = false

Maybe another issue is: is your Firefox able to play .mov media natively without QuickTime, because the regular release of Firefox 52+ only allows one plugin, which is Flash. The Extended Support Release (ESR) of Firefox 52 will still run Java, Silverlight, QuickTime, etc.

More information on this change and where to get the ESR version of Firefox: Why do Java, Silverlight, Adobe Acrobat and other plugins no longer work?

From your perspective as a website publisher, this may be the end of the road for .mov media as a practical matter, unless you are okay with providing download links to play it offline in QuickTime or VLC. For web usage, H.264/MP4 is widely supported now.