Strips the junk that design apps leave behind, rounds long numbers and removes scripts. Then it draws both versions and checks they still look the same.
Scripts, event handlers and javascript: links are always removed, so the result is safe to paste into a page.
It shouldn’t, and the tool checks. It draws the original and the cleaned file, compares them pixel by pixel and tells you if anything moved. If it did, try more decimal places.
If it means something, yes: give it a name so screen readers can announce it. If it’s decoration next to text that already says the same thing, mark it decorative so it’s skipped.
No. Your SVG is read, cleaned and compared in your browser, and nothing leaves your device.