Qt5 Configuration Tool (qt5ct)

I'm posting this here because I've not had any luck in the Applications section. I wonder if people who are more familiar with LXQt will be able to answer:

I'm confused by qt5ct in the LXQt edition.

By default when it's run it displays the message:

The application is not configured correctly.
The QT_QPA_PLATFORMTHEME environment variable is not set correctly (current value: lxqt, required value: qt5ct).

Why is it broken by default?

I can see that ~/.profile contains the line:
export QT_QPA_PLATFORMTHEME="qt5ct"
but this is clearly being ignored:

echo $QT_QPA_PLATFORMTHEME
lxqt

So presumably there's no point in this line being in ~/.profile.

If I add QT_QPA_PLATFORMTHEME qt5ct to the 'Environment Variables (Advanced)' section of 'LXQt Session Settings' and log out/in, then it does change:

echo $QT_QPA_PLATFORMTHEME
qt5ct

But then the theme becomes completely broken, and no amount of tinkering in 'Qt5 Configuration Tool' can fix it. For example, all the menu, desktop and file manager icons vanish, the file manager becomes unusable and the 'Show Desktop' panel widget turns into a big bar that says "Show Desktop"

In this post, it says that "You don’t need qt5ct on lxqt."

So what I'm wondering is: In light of all this, was it a mistake to include qt5ct in the LXQt version of Manjaro? Should I remove it? It's inactive by default (and this seems unintentional), and when it is active the desktop is unusable. If it wasn't a mistake to include it, why is it included?

A post was merged into an existing topic: I am confused by 'qt5ct'

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