URL: https://ok.ru/game/knightsclash

Browser / Version: Firefox Nightly 69.0a1 (2019.06.02)
Operating System: Windows 10 Pro
Tested Another Browser: Yes

Problem type: Site is not usable
Description: Game doesn’t play

Prerequisites:
1. OK.ru account created and signed in.
2. Adobe Flash enabled.
Steps to Reproduce:
1. Navigate to https://ok.ru/game/knightsclash
2. Observe behavior.

Expected Behavior:
Game plays.

Actual Behavior:
Game doesn’t play.

Note
1. Not reproducible on Chrome 74.0.3729.169.
2. The issue is reproducible regardless if Tracking protection is enabled or not.
3. Screenshot attached.
Console:

Invalid URI. Load of media resource failed. 2 knightsclash
Ignoring unsupported entryTypes: longtask. 63d6653d.js:1:2672
No valid entryTypes; aborting registration. 63d6653d.js:1:2672
flash version 32, start timeout iframe:283:11
SecurityError: Permission denied to get property "href" on cross-origin object swfobject.js:4
SecurityError: Permission denied to get property "href" on cross-origin object

Watchers:
@softvision-oana-arbuzov
@softvision-sergiulogigan
@cipriansv

sv;

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