fix: avoid running load function on invalid requests

[teemingc]

fixes #9217

Checks that the request method is either a GET, POST, or HEAD before attempting to render the page.

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[benmccann]

I just noticed a blank line on line 329 of respond.js (which used to be line 327) while looking at this PR. Maybe you can remove it while you're editing the file

I feel like my brain is probably just malfunctioning at the moment and the answer will be obvious, but when would you use a POST instead of a GET to render a page? Is it something to do with content negotiation or progressive enhacement?

[teemingc]

I just noticed a blank line on line 329 of respond.js (which used to be line 327) while looking at this PR. Maybe you can remove it while you're editing the file

Ah found it and removed it.

I feel like my brain is probably just malfunctioning at the moment and the answer will be obvious, but when would you use a POST instead of a GET to render a page? Is it something to do with content negotiation or progressive enhacement?

Yeah, the POST method is for those progressive enhancement / action requests.