How to play alarm sound in browser?

Hello,

I have one problem. I am sure that I am overlooking something obvious, but I am not able to find a solution.

In HA, I implemented the thermometer with threshold alarm. I preset some temperature and as soon as the temperature measured by sensor exceeds the preset value, the Trigger is activated and NSPanel.rtttl service plays an alarm sound at the Sonoff NSPanel. This part works OK.
But I would like to add another action to this trigger, which will play some MP3 alarm sound on my PC (which is in another room) through my Firefox browser which has a HA page opened in one Tab.

Is there any way how to do that ?

Thx for any idea.

You can probably do what you’re after with Browser Mod.

Browser_Mod can do it, but last time I fought with it I gave up.
I do not know if it has been improved, but before it would give a new identity to the browser whenever the browser was updated, which happens a lot now a days, so I constantly had to update the script/automation.
There might be ways to handle it, if your setup of browsers is simple. Mine wasn’t.