Suggestions from Igor

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Need to check that
   a) these dlls are loaded from location you are going to install to. If they are loaded from elsewhere you do not care?
   b) may need to check for deployment toolkit dlls
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"
At least some of the current browsers load plugin in the new processes. E.g. plugin-container for firefox.

IMHO, accurate logic will be to see if it browser process or one of the parent processes is browser process.

Also, there other "builds" of FF and Chrome and .exe file name may be very different. Especially localized builds.
We may want to enhance detection to be based on what else process loads (e.g. chrome or ff all).
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