[Bug]: qt5 xdgdesktopportal platform theme not working

[813ethan]

Problem description

when the xdg-desktop-portal platform theme (provided by qt5-qtbase) is chosen in qt5, the file picker dialog is not showing

screen-20250118-221108.mp4

What steps will reproduce the bug?

Step 1
install any qt app
run any qt app with QT_QPA_PLATFORMTHEME=xdgdesktopportal <app>

or

install qt5ct
in qt5ct set "Standard dialogs" to "XDG Desktop Portal"
run any qt app with QT_QPA_PLATFORMTHEME=qt5ct <app>

Step 2

use any functions involves the file dialog in the qt app

What is the expected behavior?

the file picker dialog shows up instead of nothing

System information

Termux Variables:
TERMUX_APP_PACKAGE_MANAGER=apt
TERMUX_APP__APK_FILE=/data/app/~~O5ZjEiaBvTrlPsAa_jH0QQ==/com.termux-EZGIDz8PWdU8SEYWgjlqGw==/base.apk
TERMUX_APP__APK_RELEASE=GITHUB
TERMUX_APP__APP_VERSION_CODE=1020
TERMUX_APP__APP_VERSION_NAME=0.119.0-b1+monet36
TERMUX_APP__DATA_DIR=/data/user/0/com.termux
TERMUX_APP__IS_DEBUGGABLE_BUILD=true
TERMUX_APP__IS_INSTALLED_ON_EXTERNAL_STORAGE=false
TERMUX_APP__PACKAGE_NAME=com.termux
TERMUX_APP__PID=25979
TERMUX_APP__TARGET_SDK=28
TERMUX_VERSION=0.119.0-b1+monet36
TERMUX__SE_FILE_CONTEXT=u:object_r:app_data_file:s0:c112,c258,c512,c768
TERMUX__SE_INFO=default:targetSdkVersion=28:complete
TERMUX__SE_PROCESS_CONTEXT=u:r:untrusted_app_27:s0:c112,c258,c512,c768
TERMUX__UID=10624
TERMUX__USER_ID=0
Packages CPU architecture:
aarch64
Subscribed repositories:
# sources.list
deb https://packages-cf.termux.dev/apt/termux-main/ stable main
# x11-repo (sources.list.d/x11.list)
deb https://packages-cf.termux.dev/apt/termux-x11/ x11 main
Updatable packages:
All packages up to date
termux-tools version:
1.44.6
Android version:
15
Kernel build information:
Linux localhost 5.10.223-gki-g99d0e21e6bd7 #6 SMP PREEMPT Mon Jan 13 18:09:39 CET 2025 aarch64 Android
Device manufacturer:
Xiaomi
Device model:
23049RAD8C
LD Variables:
LD_LIBRARY_PATH=
LD_PRELOAD=/data/data/com.termux/files/usr/lib/libtermux-exec.so
Installed termux plugins:
com.termux.widget versionCode:1000
com.termux.window versionCode:15
com.termux.x11 versionCode:15
com.termux.styling versionCode:1000
com.termux.api versionCode:51
com.termux.boot versionCode:1000