The desktop app is the only version that can open any folder on your computer — including the ones a browser refuses to touch.
Eather is not signed with a code-signing certificate. Those cost a few hundred dollars a year, and until one is bought, Windows treats every new program from a small developer as suspicious — not because it found anything, but because it has never seen the file before and nobody has paid to vouch for it.
You may see any of these:
Do not take that on trust. Check it yourself:
Eather will never ask you to turn off your antivirus. Anything that does, should not be trusted.