Silently install voices for a ttsEngine extension
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I'm creating a speech extension for my webpage in order to make it accessible for blind people. This works good so far, now I wanted to have the two voice engines I picked installed automatically. And this has proven to be really difficult:
I've been through tons of info on how to approach this. The easiest way would be to just open the voice (ttsEngine)'s web page in the Chrome store - but then the blind people would have to go through all this hassle as well.
Most other approaches require computer permissions I do not have, e.g. messing with the user's file system or registry.

My question: Is there really no easy way to require, include or preinstall another extension for your extension, so it installs in the background (silently)?

Thanks for hearing me out and providing some help!
Kind regards,
Roman