Get rid of the error:
Resource interpreted as Script but transferred with MIME type text/plain: "blob:null/[…]".
when loadind the workerscript by creating the Blob with "type" : "application/javascript":
Added 'bool' support to user editable parameters
The parameter will be displayed as checkbox in the generated form.
For default values of type other than boolean an error will be displayed.
In the user script the value can be used as boolean.

example:
{ name: 'check', caption: 'awesome?', type: 'bool', default: true }