Choose a tool and use your mouse to draw. Press E to clear. When saving, use triple click to select the entire code. Copy it and paste it into your browser's address bar to open the image which you can then download. Save the code too (for example into a text file) because it will make loading it later to continue editing easier. Pasting the code you got when saving is the easiest way to load an existing image. If you have the BMP/DIB file but not the save code, you can upload it to http://tomeko.net/online_tools/file_to_base64.php?lang=en and paste the result.
This is similar to the previous version ( https://scratch.mit.edu/projects/322213242/ ), but completely rewritten and much more complete. It still needs performance optimization. Updates: 2022-05-17: beta ✏️ initial release 2024-02-24: version 1 ✏️ undo & redo ✏️ better color picker ✏️ the circle tool now shows a preview ✏️ purple buttons