Huge pasted CSS breaks the app an second run

If you paste a larger CSS file (around 1600 lines) into the input field, the first submit works as expected.
On second submit, this error is thrown:

> There was an error -- shocking, I know. If you've got a minute, please report it!
> Request Arguments
>
> {
> "url": "",
> "browsers": "",
> "css": "[huge pasted css ...]"
> }
>
> Error
>
> {}
>
> fetch/<@http://www.doiuse.com/bundle.js:3295:19
> once/<@http://www.doiuse.com/bundle.js:3169:12
> loadFunc@http://www.doiuse.com/bundle.js:3064:9
> readystatechange@http://www.doiuse.com/bundle.js:2994:13

If you try to report this error using the "report it!" link you get:
> 400 Bad Request
> Request Header Or Cookie Too Large

I think to fix this, the pasted CSS should not be submitted as GET parameter, but using POST.