Contact
Bug reports, files the tool could not clean, and questions about the method are all welcome. Most of what people write in about is answered further down this page, so it is worth a look first.
Send a message
Use the form and a reply will come to the address you give. There is no account and no ticket system behind it.
Worth being explicit about, since the rest of the site makes a point of it: the tool itself never uploads your files, but this form is an ordinary form. What you type here is posted to this site's own server and sent on by email, and no third party handles it. Do not paste anything sensitive into it, and do not attach the file itself. Its dimensions and where it came from are what help.
A file it could not clean
If an image or a clip comes back untouched, or with residue still visible around the mark, the detector did not find a watermark it was confident about. That is deliberate rather than a failure: the tool declines instead of altering a corner it does not understand.
Two things usually fix it. Use the original download from Gemini rather than a screenshot or a re-export, since both re-compress the mark before it reaches the tool. And check that the file is at one of Gemini's standard output sizes, because non-standard crops move the mark away from where it is expected.
The full list of causes, and how to tell which one you have, is in why a file sometimes comes back unchanged. The size list is in every official Gemini image output size.
Video that will not process
Video needs WebCodecs H.264 encoding, which today means Chrome or Edge on the desktop. Safari and Firefox can play the result but cannot produce it. If the page reports that your browser cannot encode video, that is what it means, and what WebCodecs can and cannot do explains why.
Long clips are slow rather than broken. Every frame is decoded, cleaned and re-encoded on your own hardware, so a clip takes roughly its own running time, and the tab has to stay open while it works.
A watermark it does not handle
The method needs the mark's artwork and its alpha map, which exist for the Gemini sparkle, the Veo mark and the NotebookLM wordmark. A watermark from another product cannot be inverted and the tool will decline it.
If a file that is definitely an unmodified Gemini or Veo download is refused, that is worth reporting through the form. It usually means a new layout or alpha variant has appeared, and those get added. The dimensions and the approximate date it was generated are the useful details.
Everything else
The guides cover how the marks are constructed and removed, what a re-encode costs in measured terms, and where the method reaches its limits. The about page goes through the method in outline, the changelog records what has changed and when, and the privacy policy sets out exactly what does and does not leave your device.