I suspect Candy Crush uses Flash in Internet Explorer, too, but because Firefox and IE use different plugin technologies, there are different installers for each browser. Since so many sites use Flash, perhaps we can help you resolve the issues you're having. You can download an installer for Flash 18.0.0.209 on this page: https://www.adobe.com/products/flashplayer/distribution3.html In the first table, look for the row for "plugin-based browsers" and you can use either the EXE or the MSI installer. To ensure that the old version is removed, please close any tabs that are using Flash, or exit out of Firefox, during the update. Then, depending on the kinds of issues you've been having, these are some common troubleshooting steps: (1) If you have any recorders/downloaders that interact with Flash media make sure they are as up-to-date as possible, or disable them temporarily. (2) Disable Flash from using hardware acceleration right-click the media player and choose Settings, then the first mini-tab and uncheck the box to use hardware acceleration. More information in this support article from Adobe: http://helpx.adobe.com/flash-player/kb/video-playback-issues.html#main_Solve_video_playback_issues (3) Disable protected mode The protected mode feature of the Flash player plugin has security benefits, but seems to have compatibility issues on some systems. There is a hidden setting for this: (A) In a new tab, type or paste '''about:config''' in the address bar and press Enter. Click the button promising to be careful. (B) In the search box above the list, type or paste '''flash''' and pause while the list is filtered (C) Double-click the '''dom.ipc.plugins.flash.disable-protected-mode''' preference to switch its value from false to true. This might not take effect until all Flash has been unloaded for a few minutes, or you close Firefox. Any improvement? ---- While you are troubleshooting this, it might be helpful, to avoid unnecessary pain on sites where Flash is not actually essential, try setting Flash to Click-to-Play ("Ask to Activate"). This will delay Flash from starting on a page until you approve it. To set "Ask to Activate", open the Add-ons page using either: * Ctrl+Shift+a * "3-bar" menu button (or Tools menu) > Add-ons In the left column, click Plugins. Look for "Shockwave Flash" and change "Always Activate" to "Ask to Activate". Then when you visit a site that wants to use Flash, you should see a notification icon in the address bar and usually (but not always) one of the following: a link in a black rectangle in the page or an infobar sliding down between the toolbar area and the page. The plugin notification icon in the address bar typically looks like a small, dark gray Lego block. When the page wants to use a soft-blocked plugin, the icon turns red to alert you to the concern. If you see a good reason to use Flash, and the site looks trustworthy, you can go ahead and click the notification icon in the address bar to allow Flash. You can trust the site for the time being or permanently. But some pages use Flash only for tracking or playing ads, so if you don't see an immediate need for Flash, feel free to ignore the notification! It will just sit there in case you want to use it later.

Gosh, some people are so smart! Thank you! I've done all you suggested and so far, so good. If it acts up again, I'll be in touch.