Another thing you can try:
chrome://settings/performance
Enable Memory Saver.
That'll dump any tabs from memory that sit idle for a long enough time, and reload the web page on that tab once you bring that tab to the forefront. That way, you can have as many tabs open as you like, and you won't exhaust your free memory.
As to swap size, give us the output of the command:
swapon --show
... as you're using your browser normally. If you've got a high number under "Used", you likely need to increase the size of the swap (which is most easily done by plugging in another USB memory stick, formatting it as swap, then setting it up to auto-mount in your fstab file... all of which we can help you with if you're exhausting your memory and swap space).
And you can try nohang:
sudo apt search nohang
nohang/focal,focal,now 0.2.0-1~oibaf~f all [installed]
sophisticated low memory handler for Linux
sudo add-apt-repository ppa:oibaf/test
sudo apt update
sudo apt install nohang
sudo systemctl enable --now nohang-desktop.service