squiggly here doc breaks try opal in browser

[rubys]

Reproduction instructions. Go to https://opalrb.com/try/#

Enter the following in the text area:

x = <<~HERE
  xxx
HERE

Press the Run button.

Note also that there is an unhandled exception in the console log.

The patches needed to fix this can be found at https://github.com/ruby2js/ruby2js/blob/f05434dba39e53f1314a57ad82f18ca8786aa866/demo/patch.opal#L43

In that same file, you can find patches needed to get diagnostics working, and to update stdlib Racc to 1.8.5.

FYI, the above patches are deployed at https://ruby2js.com/demo