Scroll text horizontally

[Saki]

The output should be on gadget !

However, it is so here that it is flicker-free on screen even if no sync takes place.
Therefore, at least on Canvas no manual sync should be necessary.
The sync also has negative effects on the speed.
On Gadget there are also no sync problems when the text is scrolled vertically.
It is only with horizontal scrolling.
Even with manual sync it does not go absolutely flicker free on Windows OS.
On ButtonImageGadget for example it doesn't work at all with manual sync, only on Canvas.
There is a connection with the processing of the WindowEvents.

Your code is not correct insofar as you do not process all events before FlipBuffers.
Nevertheless it works, at least on WinOS.

It is an WinOS problem, it does not occur on Linux and Mac !