In each of these cases, one or more square brackets and/or curly braces appearing in a production is in serif font, should be in sans-serif. (I've marked the offending characters with underscores.)
13.4 / Syntax / prod 1
ExpressionStatement[Yield] :
[lookahead not-in {{, function, class, let [ _}_ _]_ Expression[In, ?Yield] ;
13.6 / Syntax / prod 1
IterationStatement[Yield, Return] :
...
for ( [lookahead not-in {let [ _}_ _]_ Expression[?Yield]opt ; ...
...
for ([lookahead ≠ let _]_ LeftHandSideExpression[?Yield] of ...
...
15.2.3 / Syntax / prod 1
ExportDeclaration :
...
export default [lookahead not-in { function, class } _]_
AssignmentExpression _[_ In _]_ ;
fixed in rev34 editor's draft
fixed in rev34
rev34 still has this one:
13.6 / Syntax / prod 1
IterationStatement[Yield, Return] :
...
for ([lookahead ≠ let _]_ LeftHandSideExpression[?Yield] of ...
...
And in this one, you fixed the square bracket but not the curly brace:
13.4 / Syntax / prod 1
ExpressionStatement[Yield] :
[lookahead not-in {{, function, class, let [ _}_ ] Expression[In, ?Yield] ;
fixed in rev35 editor's draft
fixed in rev35