The location of the mms.cfg file depends on the operating system and the browser in use. You need to create or edit this file:”mms.cfg” For more information, see the Enterprise enablement support section of the Adobe Flash Player EOL Enterprise Information Page.
The Enterprise enablement functionality available in Adobe’s latest releases of Flash Player can be used to allow content from specified sites to be displayed. besides an independant rollup it’s also possible it is included in a rollup package so watch out when updating!
This option only works if you haven’t installed KB4577586 on your system because when that update is installed it’s no longer possible to run flash on your system.
Thats all great but what if for example your vCenter is version 6.7 or lower. To see the official Adobe newsitem read this item: Adobe Flash Player End of Life Since 31 december 2020 Flash is end of life and since 12 januari 2021 it is blocked in browsers and automatically removed via windows update.