unable to uncomment a commented function value

[meetar]

To replicate:

• Give a parameter a multi-line function value:

priority: |
    function() {return feature.scalerank}

• Place the cursor on the line with function() OR select multiple lines including the line with function()
• Enter command-/ to comment out the line
• Enter command-/ to uncomment the line

Result:

When commenting, the entire function turns green, and the selected lines are prepended with // – but when uncommenting, nothing happens.

Expected result:

Only the selected lines or the line with the cursor will be commented, and uncommenting will uncomment them.