This is not a recommendation or advice about how you should use spot for browsing, but simply an explanation of how I use it, and I am sharing it in case it is of interest to anyone else.
I use several different browsers for different tasks, and almost all of the time I use them as the root user. I know...there are many who will point out the potential security implication of this. (Perhaps foolishly) I believe myself savvy enough to understand the risks and avoid them with good browsing practices.
However, there are some situations where I need to click on a link where I don't really get the opportunity to ensure that the purported destination is as expected - e.g.
In an application I might click on the 'help' or 'check for update' options, or the 'visit the website' option
I might click on a link in an email
I may download some attachment from the web which opens automatically using the default browser
etc
These are the situations where I want to use spot for the browser - so this is what I have done:
I use LibreWolf (the appimage) as my default browser
I store the LibreWolf.AppImage in my "applications" directory along with all the other apps I use
In that directory I have a symlink LibreWolf pointing to the LibreWolf Appimage I am currently using
-This symlink has been assigned to user spot using the 'chown' command eg chown -h spot:spot LibreWolf
-I have created a small script named run-librewolf-spot.sh and assigned it to spot using the 'chown' command
-This script executes the command - run-as-spot /mnt/home/my-applications/programs/LibreWolf/LibreWolf --profile /home/spot/.librewolf "$@" &
When the script is first executed it will create the file .librewolf in /home/spot
I know that some people would not like this because it adds the librewolf profile into the save folder/file and increases it's size. But - I like it this way because if I ever have to restore my save folder/file from a backup, then this default browser profile is also restored and I don't have to do anything extra.
In /usr/local/bin/defaultbrowser I have changed the command to execute this script eg exec /mnt/home/my-applications/programs/LibreWolf/run-librewolf-spot.sh "$@"
In the menu Setup - Set Default Apps - I have set the default browser to /mnt/home/my-applications/programs/LibreWolf/run-librewolf-spot.sh
So, whenever I click on a link which invokes the default browser (usually done by executing the xdg-open command) it will open the link in my 'spot' user version of LibreWolf.
Whenever I want to update the LibreWolf appimage,
I delete the current appimage (or rename it to .previous)
then after downloading the latest appimage I use the 'chown' command to assign it to the spot user ie chown spot:spot LibreWolf.x86.AppImage
That's it. Any application or link invoking the default browser will be opened in the spot version of LibreWolf.