New issue
Advanced search Search tips
Note: Color blocks (like or ) mean that a user may not be available. Tooltip shows the reason.
Starred by 24 users

Issue metadata

Status: Verified
Closed: Jul 2017
EstimatedDays: ----
NextAction: ----
OS: Linux , Windows , Chrome , Mac
Pri: 1
Type: Bug

Blocked on:
issue 693739

issue 696790

Sign in to add a comment

Remove "Prefer HTML over Flash" from chrome://flags

Project Member Reported by, Apr 7 2017 Back to list

Issue description

Given the complete launch of HTML(5) by Default and the upcoming settings unification, we should also remove the flag to disable "Prefer...," since the behavior is no longer considered an experiment.
Blockedon: 693739
Do we still need this flag until we can re-enable this feature on all ChromeOS devices? (To allow admins to test on ChromeOS in advance of our re-enabling by default).
Yes, that's probably fair (and very good observation).  We need to sync back around w/ their Enterprise folks to see if they've added the necessary configuration in CPanel.  60 maybe too aggressive for this change.
Not so fast, please: for whatever reason MLB video won't even play if you have "default" on the setting. They insist you change it to "disabled" to even be able to see their video. It sucks, but I'm paying good money for that, so please don't change it.
Toggling that flag is dangerous since it allows Flash Player to run on all sites on the web (i.e. not just MLB), rather than just restricting it to origins that need it.  That recommendation unfortunately opens users to security issues and highlights why that flag needs to be removed.

(If that's their recommendation) MLB will either need to update their instructions to use site exceptions (, which are quickly accessible from the lock icon next to the site address, or present a link to (download|enable) Flash player, which when clicked will enable Flash for that particular site... both of which are simpler than going into about://flags.
Project Member

Comment 5 by, Jul 21 2017

The following revision refers to this bug:

commit edb4808c66183027797e48416f60c3802fb62796
Author: Tommy C. Li <>
Date: Fri Jul 21 00:32:34 2017

[HBD] Remove HBD and Run-all-Flash from chrome://flags

These flags existed in chrome://flags as an escape hatch for users
during testing.

Now that HTML5 by Default has completely launched, they are no longer

Bug:  709550 
Change-Id: I1a140a86581483913681055c246a0c2509d783c2
Commit-Queue: Tommy Li <>
Reviewed-by: Anthony LaForge <>
Cr-Commit-Position: refs/heads/master@{#488516}

Project Member

Comment 6 by, Jul 21 2017

The following revision refers to this bug:

commit 71bce333b862b8def630b2c581a54e28a5042308
Author: Tommy C. Li <>
Date: Fri Jul 21 16:57:10 2017

[HBD] Remove the "Run all Flash in Allow mode" feature.

We've already removed access to this feature from chrome://flags.

This just removes the now-dead implementing code.

Bug:  709550 
Change-Id: I21cd2516874722525c2ddab4a2ab0840e46d38c4
Reviewed-by: Bernhard Bauer <>
Commit-Queue: Tommy Li <>
Cr-Commit-Position: refs/heads/master@{#488683}

Should we flip this to Fixed?
Status: Fixed (was: Assigned)
Yes! Thank you for the reminder.

Comment 9 by, Jul 26 2017

Labels: TE-Verified-61.0.3163.13 TE-Verified-M61
Adding the verified label as well as 'Prefer HTML over Flash' is not present on chrome version: 61.0.3163.13 on Windows-10, Mac OS 10.12.5 and Linux Ubuntu 14.04.
122 KB View Download
laforge@: does this need to fix in M-60?
Labels: -M-60 M-61
Nope, no need to merge it back.
@hsiangc - Thanks for checking!
Status: Verified (was: Fixed)
Verified with 9765.28.0/61.0/3163.41

Comment 14 by, Aug 16 2017

So - I see this issue is closed... but I am confused. The main issue talked about removing the Prefer HTML over Flash flag which I get is redundant with the new settings... the the #run-all-flash-in-allow-mode flag is also being removed but is no longer supported it would seem.

We have a legacy application that we are planning to completely replace over the next two years that still uses "hidden" flash objects as part of it's infrastructure and there is no longer any way to enable those with that flag removed.

Is this intentional or an oversight? For our customers on desktops we can just send them to FF for now - but without an ability to enable this flag our ChromeOS customers are going to be SOL., contact me (contact form at -- I have some ideas for you...
bken / The problem is with the K12 OLS system.  I signed in, took a look at the web pages, and was able to fix the pages after the fact and run Flash.

Just have your developers fix -- crazy easy.

If your "customers are going to be SOL" -- it is solely due in inaction on the part of K12.
The "prefer-html-over-flash" flag is a solution to making flash work in incognito mode. This was cited by Adobe staff about 6 months ago.

Now that it's gone there's no way to use Flash in incognito mode. Is this intended?

Comment 18 by, Sep 13 2017

@jerusanders - My recommendation would be to use the site settings menu, which you will find by clicking the icon (usually a lock or an i) in the url bar, next to the reload button.  In there you can enable Flash Player to run for a particular site.

Because incognito mode effectively is only a temporary profile, those preference selections will only exists so long as the incognito window(s) is open.

Comment 19 by, Sep 14 2017


The site settings menu is bugged in the incognito mode. The only way to get flash to work on incognito is through the removed flag 


Yeah, it doesn't work, it seems to ignore the site settings menu. Even "Click to run Flash" thing just causes the page to refresh with the flash still blocked.
Confirmed, with the flag removed I cannot enable flash video in incognito mode.

Comment 22 by, Sep 15 2017

I'm not able to replicate that behavior in incognito (i.e. all forms enablement prompts work properly).

If there is a specific site that does not work properly in incognito, please file a separate bug.
I have the issue in icongnito mode as well, earlier it was only this setting "Prefer HTML over Flash" tha fixed it and it's definitely removed now in 61.0.3163.91! Let's hope that we find another workaround soon!
Trouble is site exceptions are not working. As a result auto playing will not work. i have to actually click on a play button to make content run. The flag that was removed in question is causing me alot of trouble now since it was removed. I personally would like to see it reinstated or turned into a setting that allows autoplay.
This needs to be reinstated ASAP. WatchTVAnywhere is unusable without this flag, as despite making flash exceptions, Flash WILL NOT WORK on those sites.
Im having a problem with a site that uses flash player. even though its enabled, it will not work. it only worked when I turned off Prefer HTML over Flash. now without it, the site will not respond to the flash player. the settings in chrome does nothing for it, even when allowed and have the site on the enabled list.
I have the same issue, the "Prefer HTML over Flash" fixed this previously for me. But as this now gone, I cannot get flash in incognito mode.

Comment 28 by, Sep 28 2017

Not sure what the intended behavior is, but enabling Flash via the 'Allow sites to run Flash' toggle or by adding domains to the 'Allow' list does not work in Incognito mode.

20170928  v61.0.3163.100 (Official Build) (64-bit)
No Extensions Enabled

Block sites from running flash -> [Check Now] -> Failure
 Incognito: Failure

Allow sites to run flash -> [Check Now] -> Success
 Incognito: *Failure*

Allow -> ADD -> -> [Check Now] -> Success
 Incognito: *Failure*

Test url:


I did a refresh of the Adobe Flash Help page each time, and did not verify a 'Failure' before adding the host name, but this should be enough to get the idea. Also, no other incognito windows were open.
I have a problem with this new version of Chrome unfortunately. One of my blogs requires Flash used I do have autoplay music on my profile, and since turning off "Prefer HTML over Flash" was the solution to this problem, that's no longer the case now it's no longer featured in Flag. 
Incognito-mode flash still not working on 2017-10-05 using google-chrome-stable version 61.0.3163.100-1 on Ubuntu 17.04.
Thanks for the feedback about Incognito mode.  One thing that's perhaps important to note, which explains the behavior, is that we treat Incognito as a brand new/ fresh profile that's distinct from the user's profile and has no inherited state/ history.  We do this so that personal information has no potential to bleed through into this mode of use.  It's still possible to enable Flash for sites in Incognito mode (i.e., using the standard activation methods).  However, because Incognito is meant to be an ephemeral session (i.e., everything clears when it closes) that has no inherited state, I don't foresee us making any drastic changes to the behavior.

Thank you again for the detailed reports and test scenarios, we understand that might not be the desired answer but ultimately want to be upfront about the rationale behind the design choice.

Comment 32 by, Oct 6 2017

@laforge (comment 31)

> It's still possible to enable Flash for sites in Incognito mode (i.e., using the standard activation methods).

Do you have time to explain how to do this? I shared my screencast earlier (comment 28, ) demonstrating that the menu options to "Allow sites to run flash" and to add a specific domain-based exception are not working.

Whether one is in incognito mode or not, the flash settings should apply.  I do not understand why this is so difficult to maintain; one has nothing to do with the other.
well looks like its time to move on to firefox...
first horrible moderation of youtube, than when ever i search for something it displays something completely different from what i expect only a bunch of ads, and now removing the ability to fix YOUR mass by using the Prefer HTML over Flash setting.
@jspraul - (Comment 32) - If you click on the (i)/(lock) icon in the url bar you can allow Flash Player to run for a particular site.  Similarly, if the developer has either a direct embed or a download link (for Flash Player) clicking on either of those will trigger the UI to enable Flash Player.

Settings, because they are attached to a user's profile, do not get carried into Incognito mode.
"Settings, because they are attached to a user's profile, do not get carried into Incognito mode."

At least one setting, home URL, does get carried into incognito mode.  I just did it.  It seems that chrome carries some into incognito but not others.  Inconsistent.
two questions...
one how dumb do you think people are that they go to tech support and/or forums without trying that?
i've tried it, it doesn't work.
second do any of you even try to do it in incognito ever?
it CLEARLY doesn't work other ways people wouldn't be here pissed off.
i know my comment is a bit aggressive and not very polite so you will ignore it, but still there is a problem, and that problem HAD a solution, a solution you removed.

The functionality of clicking "always allow on this site" then refresh does not work in incognito mode. It's a broken feature. 

Comment 39 Deleted

Comment 40 Deleted (re comment 32) This is so not true. There are all kind of stuff such as bookmarks, browse history, and even password autofill inherited from the regular sessions. Other content privacy settings are inherited as well (e.g. location). The interesting exception is flash.

And as all others attested here, what you suggested to change the setting for the current session using the (i)(lock) drop down doesn't work. It has no effect in incognito mode thus makes Chrome not functional for a lot of sites in incognito mode.

Comment 42 Deleted

Please see the attached gif for why the proposed "solution" you keep parroting isn't helpful.
758 KB View Download
This "issue" will resolve itself in two years from now.
Can someone just fix the "Allow site to run flash" issue already. I've tried everything suggested but it seems nothing works. Is the problem that incognito mode doesn't save any variables for the session making it so the enabled flag doesn't stick or what? Flash ran just fine in incognito mode a few months back. Either bring back the old solution or make the function that allows flash to be enabled/allowed to run on a site do what it's supposed to do.
Currently, Flash sites must be re-whitelisted after each incognito session is started (chrome://settings/content/flash -> [ADD] button next to 'Allow'), checking 'Current incognito session only' (see attached screenshot). Unfortunately this setting is not preserved for future incognito sessions.

To let Google know this issue is important to you, click the 'Sign in' link on the very top right (or bottom) of the page, then click the ⭐ (star) icon in the top left corner next to ' Issue 709550 '. Adding a comment is not recommended as it sends an email to everyone; in spite of the UI clumsiness stars get more attention long-term than comments.


Steps to reproduce:

20171110 No Extensions; No Existing Incognito Session
Version 62.0.3202.89 (Official Build) (64-bit)

Allow -> ADD -> -> [Check Now] -> Success
 New Incognito session: *Failure*

New Incognito session
Allow -> ADD -> (Current incognito session only)
   -> [Check Now] -> Success
 Existing Incognito session: Success!

Test url:

Current incognito session only.png
29.0 KB View Download

Comment 47 Deleted

Comment 48 Deleted

That fix does not work for me. It is not possible for me to run flash in an incognito window, even manually adding it to the list does not allow it to function.

Sign in to add a comment