>>/32063/
Usually it's total per post.
367,000,000 bytes according to  >>/29663/

Here's a CSS rule to remind of this (text is non-selectable unfortunately):
#labelMaxFileSize:after {
    content: ' (367,000,000 Bytes)';
}
Disabling JS helps, but probably using something less complex and memory hungry than a browser to upload is even better.