Note: `Test suite` make use of the two sample scripts `import1.js` and `import2.js` to access variables, functions and objects.
You must understand the web workers limitations/requirements when writing code to be run inside them and you must know - if the web workers are not available - the script files will be loaded inside current page and the execution context will be the current window object.
`Process a long task` will hang your browser when used without web workers support (depending on your hardware)!
`Find prime` will execute a small piece of code for each number (as a separate task), this way - even if there is no web workers support - there will be some free resources left for others to consume (done using `setTimeout`).

The progress bar should update even when web workers are not available (if the code was split in small tasks that can be run within `setTimeout`):

Check the console for errors thrown from the web workers (when running `Test suite`).