html - Is './' a valid path to submit a form to the same page for processing with PHP?

Question

I am submitting an HTML form to the same page to handle with PHP and figured out that I can use action="./", which works fine for me so far (in a test environment).

I am a little unsure though because all the examples I find recommend using either action="" or action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>"

I don't want to use action="" because the HTML Standard specifically states

The action and formaction content attributes, if specified, must have a value that is a valid non-empty URL potentially surrounded by spaces.

Is there any reason not to use action="./"? It seems better (more readable, less PHP) to me but it's confusing me that all the examples I find recommend the PHP approach.

Answer 1

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