We can't have good things, can we, SVG implementations??? Apparently, I can't re<use> anything from adjacent file, because only Inkscape understands it. Or to seek support in browser, server is required to see a group from one SVG file in another. Why?

Imagine I could just embed a link to some local file inside a random SVG and use content from that file - I could read all kinds of people's files and potentially upload them to my server without users knowing anything about it. That's why you cant use adjacent files in SVG unless you access them through some kind of server. It's basic security, deal with it.

@hitko Oh yes, I remember that one. But SVG is a well known type and just random file with random header won't suffice. First all, there is "<?xml version="1.0" encoding="UTF-8"?>" or "<!DOCTYPE..." (well, it's natural for interpreter to have a basic knowledge of what it's going to insert, and it's definitely not an executable file). Unlike HTML files, there is nothing special about SVG that makes them a source of personal information and etc.
I don't get why this can't be implemented at least with 1-2 levels of relative directory nesting level limit. 🙁

@vintprox A diagram of business data might be saved as an SVG. Or an unfinished / unpublished design. A (secret) floor plan.
While it is less likely to contain PII, it is not that unlikely to contain other secret data.

@sbiewald you beat me. Good point there.