Right click (in a flash game) => settings => Untick "Enable hardware acceleration"
If it doesn't work, you can go in settings (from your browser) => add-ons => Find Shockwave player and select it => untick "Enable Adobe Flash protected mode" .
You may need to restart your browser.
If it doesn't work, you can go in settings (from your browser) => add-ons => Find Shockwave player and select it => untick "Enable Adobe Flash protected mode" .
You may need to restart your browser.