>Invoke-WebRequest -Uri $url -OutFile $output
On *nix you might have curl or wget installed.
On Android and iOS use their respective app stores.
However, considering the scenario on the question, I would assume that browser vendors would create very easy-to-remember URLs so you could get their browser without having to memorize 100-character-long URL e.g. mozilla.org/firefox.[exe,bin,sh,deb]
curl -o fi.exe -L -C - "https://download.mozilla.org/?product=firefox-stub&os=win64&... && ./fi.exe
Other Linux OS, consult your package manager of choice.
Mac should have curl or wget that you can use (plus safari, but we'll ignore that).
Windows has Invoke-WebRequest in Powershell that you can use (plus IE/Edge, but we'll ignore).
You can do a Google search with those command line tools to find the firefox install page and download the installer.
What prompted this question? Real problem?
sudo apt install firefoxI seem to remember that the Nintendo Switch has one of these 'hidden' browsers.
doesnt exist, either its fully functional and has a browser, or its missing operating system.
Linux, e.g. 'sudo apt install snapd', then 'sudo snap install firefox' (https://snapcraft.io/install/firefox/ubuntu)