I think both use HTML5 players, so that's where the problem lies.

Could you access about:crashes in Firefox and dig up some crash reports? Those should shed light on what could be going on.

Here are some workarounds you can mess with in about:config, https://forums.opensuse.org/showthread.php/508930-Firefox-crashing-when-playing-html5-video-or-similar, but workarounds are just that - they may cause issues further down the road when you forget to reset them for the next Firefox release.

Workarounds for future reference: Try to set media.gstreamer.enabled to false in Firefox's about:config. + Changing the media.mediasource.enabled and media.mediasource.webm.enabled keys to true in about:config will get you higher quality YouTube videos back.

@Phoxuponyou:

Note that the OP is on Windows and not on Linux what the article you posted above is about, so disabling GStreamer support wouldn't apply, but media.mediasource.* could have effect.

You can also try to toggle these prefs on the about:config page:

• media.windows-media-foundation.enabled
• media.directshow.enabled

Start Firefox in Safe Mode to check if one of the extensions (Firefox menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: Firefox menu button/Tools > Add-ons > Appearance
• Do NOT click the Reset button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Ah, my bad - disregard that bit then. I've been shuffling back and forth with Windows and Linux today, so I glossed over some important factors here.

this are some of my crush reports..now what?

bp-c40953af-e3e9-44f6-a4b4-a20a42151213 bp-9c15ee6a-0ced-4cae-9a78-810812151213 bp-7ce3328c-2c9b-401b-bf2c-b6d952151211 bp-5db9a732-8d4d-4815-a1e6-3296a2151209 f4195241-73e1-44e1-914e-db9ed83fb782 bp-2e6bb72f-e535-493a-bfbe-dd4ec2151206 bp-1fc10108-23dc-49d2-83e3-63d402151206 12/6/2015 14:58 bp-0f398865-90ce-4a08-8c1f-ed02f2151206 12/6/2015 13:13 bp-ba6d4b4c-308e-49fb-a1fb-6a21a2151206 12/6/2015 12:20 bp-02034fc4-401d-499d-a954-27d872151204 12/4/2015 21:26 bp-104c3587-1365-4f0e-b4b2-65ab52151204 12/4/2015 20:15 bp-3bad0aa4-8718-40dc-b269-bbda32151204 12/4/2015 16:06 bp-2bdc85d0-a298-4750-97d0-54eb52151204 12/4/2015 13:33 bp-03c10c59-2a71-42a9-84bc-d25902151204 12/4/2015 10:09 bp-8f2120bf-5de5-470e-9986-541772151125 11/26/2015 01:10 bp-72f6faf3-7698-45bb-b563-873d22151118 11/18/2015 18:26 bp-3e6337d3-8730-4233-ad20-d60892151118 11/18/2015 14:40 bp-43efdc10-15bf-4fd2-9462-f5eaa2151118 11/18/2015 11:48 bp-5fd2a302-73f4-40b4-9e3b-e78952151118 11/18/2015 09:48 bp-4bfdc2f9-abb9-4e2b-afdb-9e7a62151114 11/14/2015 20:54 bp-9bad2319-8576-4e24-9a4a-c1c752151114 11/14/2015 10:14 bp-cd6262b7-4303-4f62-b05a-1d18e2151113 11/13/2015 13:16 bp-14c39fd2-ea59-4afb-a5c5-0d1362151113 11/13/2015 11:28 bp-16927506-239f-4a11-abaf-8a04d2151108 11/8/2015 09:46 d8c5a160-9283-44ce-ae1a-2e702272255c 11/6/2015 23:42 bp-2141573d-1b2b-4258-ada7-ab1a52151106 11/6/2015 09:59 bp-c12aeafc-87de-40b4-bd98-d95f42151028 10/28/2015 23:43 bp-6fa933eb-9da8-4a59-849f-1e82d2151025 10/25/2015 10:35 44677593-1c99-4833-9faa-641430188453 10/25/2015 01:53 bp-f214db3b-92da-46c1-ac8a-135632151023 10/24/2015 01:28 bp-faa3d2ab-8603-4e1f-b026-383b52151022 10/22/2015 07:50 bp-8cd751cc-b706-4bb5-9b80-41a882151015 10/15/2015 11:45 bp-8c0f886a-4eb5-4c66-a688-dfd622151014 10/14/2015 07:26 bp-822f9cd0-17f4-47c3-8c81-e8ad72151012 10/13/2015 01:39 bp-3439438c-5a11-42c2-92ef-830622151012 10/13/2015 00:54 bp-729370eb-4bb6-4815-9dc9-9b73a2151010 10/11/2015 01:56 bp-c8ab7ed2-b4bd-4cf3-94f5-af3fa2151010 10/10/2015 23:01 bp-7ad4c07a-d50a-4cb6-9f86-93fc72151009 10/9/2015 12:58 bp-0f91518e-10e9-40a6-971d-601592151008 10/8/2015 16:40 bp-6a3cfcb4-e8d9-48e4-a99b-a65c52151008 10/8/2015 14:49 bp-a85f1a26-7c7b-4820-86fb-615822151008 10/8/2015 07:07 bp-d59b0093-ed85-4456-980a-428fd2151007 10/7/2015 12:44 bp-0d826599-df1b-418c-bfc6-6dad82151006 10/6/2015 13:33 bp-fd487efb-5562-48cd-95e3-42edf2151006 10/6/2015 12:18 bp-482033d2-d254-450c-a3ea-9f5fe2151006 10/6/2015 10:32 bp-54cf2f8b-43e0-42e3-b00c-833852151006 10/6/2015 09:38 bp-9f2a3a51-c213-48c5-b128-555b52151005 10/6/2015 01:59 bp-899aed69-37a2-4563-9c1c-292f22151005 10/5/2015 18:08 cf84f648-3f5a-409e-8d14-0ab8bc495595 10/5/2015 12:34 bp-f79182e5-795d-4c5e-8437-065a62151004 10/5/2015 00:26 bp-ec0a191f-3a0a-4074-9fca-0ddfe2151003 10/3/2015 13:42 bp-224adc5c-dcd8-4fe8-bc10-6fed52150928 9/28/2015 17:37 bp-1a5268fe-746c-4d99-afc2-a81f32150927 9/27/2015 10:53 bp-1ed5c1ff-6f46-4311-9480-f5f7c2150927 9/27/2015 08:55 bp-b1064838-6d6b-4b38-b086-d13f52150925 9/25/2015 16:03 bp-9e21e11e-a9fb-4b45-a75f-0feaa2150923 9/23/2015 22:54 bp-1c1cecbf-90e8-4d8b-81bb-223002150921 9/21/2015 11:31 bp-9c4a87c9-fa70-492f-8104-a3d1d2150912 9/13/2015 01:23 b57c8e4d-c20a-4a2b-b22d-98e7db22b304 9/12/2015 11:46 bp-d08901c2-1fc0-4926-ae22-674462150911 9/11/2015 12:59 bp-74884488-7f19-4ff5-99aa-b51da2150910 9/10/2015 09:00 bp-8ce9314f-6d1b-43b2-9998-5f0fb2150907 9/7/2015 13:24 290eedcd-42b6-483a-91b9-018049290efb 8/31/2015 18:50 bp-7d4e4f0a-4b7b-4cd5-997a-9dd4d2150831 8/31/2015 04:21 bp-f3d8d226-f270-4417-a02f-2fbfe2150830 8/31/2015 02:58 c508727b-f43b-4034-beb3-e85990678151 8/30/2015 08:29 bp-a0c3d823-8bfb-43b6-b5e9-11fa72150828 8/29/2015 02:45 0d44baf7-5e6c-48c9-97f5-dcce07bf89bd 8/26/2015 09:16 bp-156712b0-8a55-4d29-aee9-cf4942150824 8/24/2015 10:42 1301b1c5-2b42-41fd-a3c0-56a181f66aaf 8/23/2015 21:48 5629e85e-5610-4f96-8459-7b994b8147b2 8/23/2015 07:19 101c9d1e-f08c-47aa-a256-66ed34c155f4 8/23/2015 00:23 bp-1c2543ad-5fbb-4bbe-b3fa-a8c002150806 8/6/2015 23:56 bp-fadc6317-d80b-435a-9a75-bc0e52150806 8/6/2015 23:13 bp-7f853980-39fe-4ecb-907e-1c5ed2150806 8/6/2015 11:23 bp-caf33d22-8d76-4dd0-9164-fcf012150805 8/5/2015 19:19 bp-7bb8da2e-b4b3-4700-a761-cceef2150802 8/2/2015 11:57 bp-af3e6557-2963-4519-aef1-e16af2150731 8/1/2015 01:04 bp-0b1f6e3f-66ef-4baf-bbd0-1ef262150726 7/26/2015 13:31 bp-96e7de26-922f-45b8-84e9-a53372150724 7/25/2015 01:52 bp-7e3bf961-8445-48bc-9eff-810ca2150723 7/23/2015 05:38 18e6579b-c9e3-4312-b235-833f6ed0de5c 7/14/2015 00:33 160ab710-e0d9-412f-80b9-f8e239ba310e 7/10/2015 20:04 cf8bcec6-759b-4928-b916-9e8a8fdc536e 7/4/2015 01:07 1cc0cddb-9ad6-4247-aa55-4f0b2bf2742a 7/1/2015 21:32 bp-c1e0d1e5-d622-48eb-a8e7-f45d52150629 6/30/2015 02:20 bp-e8b16295-ca0a-42dc-8a43-2088d2150627 6/27/2015 11:59 bp-d7e4bc18-57b5-45ce-81c1-1109d2150620 6/20/2015 11:51 bp-8c12140d-215a-4fb0-a1cc-bf1172150615 6/15/2015 03:32 bp-0ebdd331-638c-4190-b234-685742150613 6/14/2015 00:20 bp-6d61f105-c680-428e-a752-a81c42150613 6/14/2015 00:11 108728ba-29a5-404d-b24a-73a4aa69af22 6/13/2015 09:11 4b4e6ff6-517f-489a-b24f-69d25d1b0f16 6/12/2015 09:50 bp-368e5466-5fab-4ad6-86d3-c21332150610 6/10/2015 17:10 bp-29262bbb-49b0-42d6-b58e-b42732150606 6/6/2015 13:42 bp-5bcaf106-8e92-42d3-a5ce-1dd612150606 6/6/2015 04:06 bp-1db28934-efb2-48cf-b3f0-2a4482150605 6/5/2015 03:43 9008c4f0-f3c2-457f-bf53-e50f4c270ffa 6/4/2015 21:42 bp-a5b1deb7-3030-43cc-8abb-3589b2150604 6/4/2015 08:56 ae27fa7f-f333-4124-9aca-3d83a9398212 5/30/2015 12:12 e54fbd1b-2185-4382-b5c6-9533df1dd10c 5/26/2015 07:21 bp-9d26f436-7d0d-4bad-b710-0e4d32150518 5/18/2015 17:06 bp-2462244a-6bfa-4709-bebf-a26132150517 5/18/2015 01:03 ec45e609-af74-40bd-9c6b-7f0fd4d013fe 5/18/2015 00:08 255ffa37-3bce-4cd9-84ef-d5eb690f80aa 5/17/2015 23:24 bp-e4517995-6189-4f3e-98f8-9b6dc2150515 5/15/2015 17:20 cb561334-d956-4990-be59-ee9cd717d681 5/15/2015 07:07 4c61799d-701f-4557-9ff3-5180df86f4f5 5/15/2015 07:05 bp-5ccbd137-0dfe-402c-b012-10c482150515 5/15/2015 07:04 1e81d4b9-94ca-41bd-af5a-cc4eea94e53f 5/15/2015 06:59 c530a133-9c5d-47ea-ab47-70178655ed8a 5/15/2015 06:45 3addfc48-efbf-4bc2-bc01-ddde2a3ee6c2 5/15/2015 06:45 17a870b0-adc5-4908-a1da-cd436681625a 5/15/2015 05:58 bp-db5dd1d9-8afc-4fa8-9b78-414112150511 5/11/2015 09:06 bp-d2a9d3cc-7ffb-4944-b0f2-343ea2150509 5/9/2015 15:18 5afff884-a0e9-44b8-8edf-ec593618b9a7 5/9/2015 14:12 d8bd890e-3286-4416-9715-d427a1d0a627 5/7/2015 02:45 bp-7bccd976-1c4b-4d06-94ed-d74222150505 5/6/2015 02:38 bp-727c603a-f334-48bf-bbd8-e640b2150505 5/6/2015 00:03 fbe317a0-bb80-4764-bffa-ef67c988c000 5/5/2015 00:59 bp-1d4171b2-41fd-4f46-ae3d-a3c422150503 5/4/2015 02:03 7f659e60-2d02-4b67-88e9-e5f294aca626 5/4/2015 00:46 d2fd4d07-6f15-4db6-9cdd-7574465e5fa0 5/2/2015 15:36 fe716229-8a79-42d3-9b40-5132178da079 5/1/2015 09:47 eb51ed9d-1bc2-4097-8330-93eb0ccfbb85 4/30/2015 20:22 bp-0bed47aa-6946-4425-8e45-3f6992150430 4/30/2015 11:21 d79ae534-d465-4779-ba58-96e6e85beb22 4/27/2015 18:56 42117eef-84a6-4a72-ac79-ff580827ad86 4/26/2015 18:48 bad01c4e-9c34-4b61-b607-08e0ee1b1b6e 4/23/2015 17:05 df1e1b06-33c6-4d68-9f5a-cd85030c8c0c 4/23/2015 16:58 bp-989deeed-f47f-4a0b-a020-b5c172150421 4/21/2015 09:53 b4c1cde7-d3f5-4412-bb4a-65a0602d67d2 4/21/2015 01:28 1039f8cf-051f-4a6c-9645-3a1c1b24fba0 4/20/2015 14:12 8b97dcc0-7fc9-4923-8274-8d28cc98a30b 4/20/2015 08:23 e4bdbadd-e1ff-47eb-ae4c-b99391b0e30b 4/19/2015 16:01 a396b80e-b5bf-4d04-96e6-b30e75edcb84 4/15/2015 00:51 89b68437-1255-42b9-a74d-b1a16defafa1 4/13/2015 01:13 bp-5345070e-8cdb-41d8-9b52-c9ac32150412 4/13/2015 01:13 b37237f1-4515-4878-aa46-5270f9fbddd5 4/13/2015 01:13 c490797f-c4e8-464c-8bb6-8bc1b8655c22 4/13/2015 01:13 bp-31e792c0-17ab-46a1-9c25-c967a2150412 4/13/2015 01:13 fd926a32-328d-4cc9-879e-a7fd91f851c3 4/13/2015 01:09 417aa912-921e-4d88-aaee-405454ad77bd 4/13/2015 00:58 258b92d6-9723-4a9f-a8fd-a168ce30f29f 4/13/2015 00:55 e363f04a-ebac-4f35-bf8d-294e70dc87d6 4/13/2015 00:50 bp-df33bfa9-7d80-4038-8435-b115d2150412 4/12/2015 20:52 4cda8b0c-59b8-47d8-b30f-d6574fe00023 4/10/2015 16:02 4a9d578f-4a92-4120-86b2-4ba4f8fca08c 4/9/2015 02:32 31dacce5-0e6f-4008-ba39-a4f1eab4e465 f5fcbb0f-53dc-42f1-80e5-58cd84c7e3db 2402fd35-df8e-4dda-9296-99a2e424f293 9c1f79c6-f0f6-4fa9-beec-80f9ca319fb8 448fe31f-70f8-4b8f-ac61-75301446145a 34cdff66-1cc9-4901-8499-5808cfa9412e b0840fa0-ec18-4efe-88e4-7dba5525883e bp-e5436a79-0e61-47da-8226-fbc122150406 58d004b2-0a14-41f0-a27a-a41b9e5657da bp-868fda18-0100-4bd0-9aa2-0034a2150406 3a44fe2b-ee58-4905-8312-f165f6a5300d bp-ea545ce5-2f1f-4a30-9787-15fe32150405 bp-72901271-f54a-4d4c-982c-1641c2150405 02bf6d00-4086-4ad1-80f2-bfa17ee8f6f2 9d48ecf6-c468-456e-a081-15ffc399f804 b4875414-7671-4578-934b-7af80dc695f0 1f71c125-07a8-4a52-bd31-325577fe79ef 15aa0738-0e4e-422e-b1b1-a4ba7f2ab90b

You can check for problems with current Shockwave Flash plugin versions and hardware acceleration in Firefox and try this:

• make sure you have the latest Flash version:
  http://www.adobe.com/special/products/flashplayer/fp_distribution3.html
• check for updates for your graphics drive drivers
  https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration
• disable protected mode in the Flash plugin (Windows Vista and later)
  https://support.mozilla.org/kb/adobe-flash-protected-mode-firefox
• disable hardware acceleration in the Flash plugin
  https://helpx.adobe.com/flash-player/kb/video-playback-issues.html
• disable hardware acceleration in Firefox
  https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

See also:

• http://kb.mozillazine.org/Flash#Troubleshooting

Thanks for the report IDs. cor-el is probably on the right track here, as Flash shows up a few times and graphics-related or hardware acceleration issues show up often (I went through a dozen or so reports).

Based on the Solutions I could find (there's a handy Search Mozilla Support for Help button in the top right corner on the crash report page), I would suggest the same list of remedies as supplied by cor-el; update Flash, GFX drivers, try without hardware acceleration.