I use this tag :
<meta http-equiv = "refresh" content = "300; url = https://idksomeurl.glitch.me/" />
it asks users to go to the URL after x seconds (here it’s 5 minutes), but it can be set to reload the same page like a ping service would.
But does it count as a ping if it reloads the same page every 5 minutes ?
Is it banned even if it’s used out of a “keep alive”/ping context ? I use it to send users out of the 404 page and back to the main page…