The proper way is to send the PDF, with the correct mime, and let the browser deal with it any way it decides to.
The stupid way for a site to act is to tell the browser to download the file instead of displaying it. And the stupid way for a browser to act is to do whatever the site tells it to do instead of what they user wants. The OP seems to have picked a stupid pair of tools.
It’s the only proper way .
Fuck your website all my homies use their preferred PDF reader.
The proper way is to send the PDF, with the correct mime, and let the browser deal with it any way it decides to.
The stupid way for a site to act is to tell the browser to download the file instead of displaying it. And the stupid way for a browser to act is to do whatever the site tells it to do instead of what they user wants. The OP seems to have picked a stupid pair of tools.