I customarily export draw.io drawings as SVG with the option to "include a copy of my diagram" selected. This enables me to display them in a SVG-capable browser, and then open and modify them further in draw.io.
I'd like to do some scripted editing of the SVG file, such as modifying the href of a link I've added to a shape, but generally anything. In my limited testing I've found that I can open one of these SVG files in a text editor, change the href, save, and still reopen the file both in a browser and in draw.io.
What worries me is the chunk of base-64 text inside the SVG file, which I assume is the embedded "copy of my diagram". Am I risking throwing the SVG out of synch with the embedded diagram, or is it safe to do this?