Thank you very much to all of you for your input !

I see port in few of your feedback.

I was not clear enough, let me rephrase:
is it possible to give a subnet to a node, not based on the port of the switch/router but based on the node ? meaning that the switch/router need to recognize the node ( MAC or login? ) and then will give him access to A or B

Thanks.

I think I found the cause.

one of the parent div have is properties perspective and it seem to be the problem… (Firefox 115*)

So I created an dirty workaround ;)

Thank you @nnullzz@lemmy.world & @bjorney@lemmy.ca & @fubarx@lemmy.ml

for those explanations ! So, as I have my hand on a raspberry , I will give a shot with that first :)

Thank you very much for your feedback @anzo@programming.dev & @rimu@piefed.social

Thanks @pietervdvn@lemmy.ml unfortunatly ikea is quite the opposite of

… ~strong …

Thanks @Max_P@lemmy.max-p.me weird because I can use XHR as async… see: https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/open open(method, url, async)