It happens only on windows with chrome.
For any reason, click event isn't correctly triggered and it seems work correctly
with pointerup.
And it seems that when drawing a svg on an OffscreenCanvas we need to wait
a little in order to be able to transfer it: it's why this patch adds
a check on the canvas content.
The main stamp button will be used to just enter in a add/edit image mode:
- the user can add a new image in using the new button.
- the user can edit an image in resizing, moving it.
In image mode, when the user clicks outside on the page but not on an editor,
then all the selected editors will be unselected.
There are 2 rotation we've to deal with: the viewer one and the editor one.
The previous implementation was a bit complex and having to deal with these
rotation would have potentially increase it.
So this patch aims to simplify the implementation and deal with all the possible
cases.
The main idea is to transform the mouse deltas according to the rotations and then
apply the resizing in the page coordinates system.
createImageBitmap doesn't work with svg files (see bug 1841972), so we need to workaround
this in using an Image.
When printing/saving we must rasterize the image, hence we get the biggest bitmap as image
reference to avoid duplications or poor quality on rendering.