Stack app w/ Material theme throws OpenGL error and renders wrong.

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Overview:

Qt Quick Stack app w/ Material themed qt quick controls turns black and logs OpenGL error when certain conditions are met. It seems that the issue is triggered whenever the window width is greater than height. Whenever the app returns to a layout where the height is greater than the width the theme appears normal.

Project setup:

1. File
2. New File or Project
3. Select Qt Quick Application - Stack
4. Select qmake
5. Select QT 5.11 and Material Dark or Material Light.
6. Build

Issue occurs when any of the following happen:

• When visibility: "Fullscreen" is added to main.qml
• When I move the window to a new workspace via i3
• When to move the window to a horizontal tile i3

What happens:

• The theme turns blackish (see screenshot below)
• Error message is logged to console.

Error message:

OpenGLFramebufferObject: Framebuffer incomplete attachment.
OpenGLFramebufferObject: Framebuffer incomplete, missing attachment.

Additional notes:

• Issue does not happen with default theme.
• Issue does not happen with Material theme on Qt Quick Application - Swipe and Qt Quick Application - Scroll.
• Issue happens regardless of how the program is launched, startx mydemo, from a terminal mydemo , exec mkydemo in .xinitrc or directly in qtcreator with build + run.

$uname  -a
# Raspbian Buster,  Pi 3 B
Linux <hostname> 4.19.66-v7+ #1253 SMP Thu Aug 15 11:49:46 BST 2019 armv7l GNU/Linux
$qmake --version
QMake version 3.1
Using Qt version 5.11.3 in /usr/lib/arm-linux-gnueabihf

This is how the app should appear:

This is how it appears: