Warn users of Browsers that block the Bridge when Bridge is attempted to be used

[My1]

MyEtherWallet/MyEtherWallet#3636
safari blocks the mixed content even if the target is localhost (where using http is reasonable), only possible avenue would be switching to webHID if possible (iirc it isnt tho), or use a different browser
MyEtherWallet/MyEtherWallet#3338
Browsers with tracking protections, such as brave might block requests from public Websites to localhost, notably Brave.
Main Solutions are either changing to WebUSB or alternatively turning off the protection for the given site(s)

[benma]

Do Safari or Brave support WebHID? I thought Chrome was the only one that did.

This library automatically chooses WebHID if available.

[My1]

okay. I thought there were a few scenarios (outside of using a browser that cannot use webhid) that forced bridge.

Brave is basically chrome with some extras, so it should go webhid (at least it does on MEW)
but for example safari does not have the option, and there a warning for the user would be useful