The screenX and screenY of the drag event in the webview are wrong

[zhu-xiaoming]

I listened to the drag event, in the dragend event, I got screenX and screenY, and found that their values ​​are wrong.

Here is a minimal reproducible example, which is a repository generated using skpm/with-webview template:
https://github.com/little-tomorrow/sketch-plugin-test

Version Information

• sketch version: 72.1
• macos version: 11.3.1

To reproduce

1. git clone https://github.com/little-tomorrow/sketch-plugin-test.git
2. Run npm i to generate the my-plugin plugin in the project
3. Start sketch, select plugin -> my-plugin -> my-command, At this time, the webview window will be opened
4. Drag the github picture in the webview to the upper left corner of the screen
5. Then open devtools through the right-click menu

Expected Behavior

Print out x: 0, y: 0 in devtools

Actual Behavior

Print out x: 123, y: 66 in devtools

Screenshots

[zhu-xiaoming]

Additional information:
I found that by dragging pictures of different sizes to the upper left corner, the final printed information is also different, basically the value of x is the same, the value of y is very different

[mathieudutour]

so on macOS, the origin is at the bottom left (as opposed to JavaScript where it's at the top left). Maybe I made a mistake when trying to convert the coordinates.

Could you have a look?

[zhu-xiaoming]

@mathieudutour drag to the bottom left corner, x: 123, y: 965