Then you could manually extract new update when needed over this local installation. EDIT: to install locally, download the compressed archive on their website, extract the Discord folder somewhere in your home, and you can start Discord executable directly, or you can also modifiy the sktop file to change the line Exec= to point to where you extracted it (you can also modify the Icon= line to point to Discord icon in the local installation folder), and move the ktop file to ~/.local/share/applications/ so it is available in your Application launcher (in theory). So other best bet is to install Discord locally so you can manually update it yourself. If you want to have quick updates to Discord, best bet is to use the AUR version of Discord so when there is an update you can update it through Pamac or any other AUR helper immediately (because community update the AUR PKGBUILD rapidly and no need to go through the distribution update normal process, but I see it is also out of date on the AUR right now).

Discord is imported from Arch, and it is out of date there too.

Install discord ubuntu