Memory mapped out and isolated (protected), allocated specifically for programs or program functions. These areas of memory cannot be accessed by other programs.
In Windows every process has its own protected memory space already. Or at least protected unless something else wants to load a file into it which can be done using OS standard methods specifically designed to extend applications / add in new system functionality.
The issue here is Start10 runs inside Explorers memory space and thus has to load into that, to achieve that we have to set a hook which gets Start10 loaded into EVERY 64 bit process. In anything other than explorer it does nothing and because of how memory pages are shared in the OS it basically uses no additional memory.
Apps like UltraMon and DisplayFusion which provide additional taskbars detect Start10 and enable support for it based on if the dll has loaded into their processes and so we cannot simply load in explorer and disable things from there.
It is worth noting that apparently Chrome would also detect shell extensions such as file icon handlers, right click handlers etc so even without that you would have the same issue with Chrome if you opened a file dialog in it and right clicked on an exe as the shell handler for Start10 would load too.
Ultimately the 'incompatible apps' in Chrome is flawed. It works from an assumption that Chrome is perfect thus anything that's not from them must be a problem. Google have long forgotten whose computer their app is running on I feel, something that Microsoft have also forgotten.
The funny thing is Google used to actively block any dlls that caused problems so if there was something causing a problem you can bet they would have already blocked it loading! Personally this makes me wonder if there is another motive for this warning stuff.