Joomla! 4.x Coding • HTTP_ACCEPT not correct

Not sure if this is a Joomla issue or PHP?
When serving images we check to see if the browser support webp using

if (strpos( $_SERVER['HTTP_ACCEPT'], 'image/webp' )

We are fairly sure that this used to work, but my fellow webmaster recently checked and we were have only been serving JPEG images for quite some time.

I checked the header sent with the HTTP request (and same on Chrome and FF) and it had

Accept: image/avif,image/webp,image/png,image/svg+xml,image/*;q=0.8,*/*;q=0.5

which seems OK. However if I log the $_SERVER['HTTP_ACCEPT'] before the above code it shows:

text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8

Which explains why the webp is not being server. This was on our production server.

So I tried on my development (WIndows) system and got different results:

The header was:

Accept image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8

but my log now shows

text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7

which means the test passes. Now I realise that all browsers have supported webp for around 4 years so the test is not really needed in any case, but it certainly seems strange!

Statistics: Posted by MrDog — Fri Jan 10, 2025 11:50 pm

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