I think porting a different webpage render engine and js interpreter could be done, but it wouldn't be a trivial effort. Perhaps the best would be simply starting with webkit as it already has some bb10 patches to it. I would prefer the chromium or firefox codebases but porting either of these without funding (or a lot of time to spare) would be doomed for failure as a LOT of things might need to be adjusted to the blackberry platform.
If it had been easy, BlackBerry folks would have done it :)
Other devs, feel free to jump in the discussion, if any of you already tried something...?
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