When using an external keyboard with an iPad the keyboard button must be pressed which in its turn shows a on.screen keyboard. This on-screen keyboard shown does however only show a auto correction bar and no keys.
Try find out if we can set hinting so this bar is not overlayed and used at all.
Reported upstream: https://github.com/kanaka/noVNC/issues/261
Seems like this is possible with native apps:
Haven't found any solution for web apps yet, though.
Need to check out this one:
The official name for the toolbar is the "form assistant."
This bug got fixed a while back.
I have verified that you don't have to use the keyboard button in the toolbar in order to be able to type using an external keyboard on an iPad.