Recently as we all are aware from End of December 2020, Flash support ended for all the browsers. And there are most of the web portals which are still not fully optimized for HTML.
Myself being handling VMware VDI, for the same reason we had upgraded our VMware Horizon to version 7.13, After upgrading Horizon admin to 7.13, We have seen Horizon Admin HTML works very slow and sometimes become unresponsive or had to refresh the browser multiple times to make it work. So had logged case with VMware Support and seems they are already working on this issues but for the workaround purpose to make Flash player work, they had provided below steps.
Create a text file with below lines and rename the text file to “mms.cfg“
EOLUninstallDisable=1
EnableAllowList=1
AllowListPreview=1
AllowListUrlPattern=https://FQDN_Of_The_Target_System/
Note: “https://FQDN_Of_The_Target_System/” is the URL which you want to access and which requires flash player
Even would like to add a Disclaimer : Follow at your own risk 😀
Once mms.cfg file is created, copy this file to below mentioned paths, if file already present than take backup of that file and replace it with the one created above:
1) %localappdata%\Google\Chrome\User Data\Default\Pepper Data\Shockwave Flash\System\mms.cfg
2) %windir%\System32\Macromed\Flash\mms.cfg
3) %windir%\SysWOW64\Macromed\Flash\mms.cfg
Voila 🙂 and flash started working and was able to access my flash based version of VMware View Admin using Chrome, for the url mentioned in the mms.cfg file.
I have tested this with Chrome version 83 and 87.
To add multiple url in mms.cfg file, you just need to add one more line with “AllowListUrlPattern=https://FQDN_Of_The_Target_System/”
For Example :
EOLUninstallDisable=1
EnableAllowList=1
AllowListPreview=1
AllowListUrlPattern=https://FQDN1_Of_The_Target_System/
AllowListUrlPattern=https://FQDN2_Of_The_Target_System/
Credit and Reference : VMware KB Article – https://kb.vmware.com/s/article/78589
Hope this post will help you with workaround to make flash player running 🙂
This article is very helpful and it worked for me