There are 100s of web based photo editors, paid and open source. How do you know they are taking yours, not someone else's or making their own with Ai?

I would imagine they all converge on common features and core implementation foundation

There have been only two photo editors that fully support the PSD format: Photopea and Adobe Photoshop. When a new one appears, which fully supports the PSD format, from an anonymous creator, it is very likely a copy one of these two. And they usually name it Photopea-offline, etc.

but does it actually fully support the PSD format or is it false advertising?

This day in age, we need to verify ourselves

Can you show us an example? How did you verify?

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