Can't run GUI on Ubuntu 26.04 with wayland: `qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""` #968

Issues, reports or feature requests related to the GUI should be opened directly on the GUI repo

• I still think this issue should be opened here

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Trying to run bitcoin-qt after upgrading ubuntu 24.04 to 26.04 and I'm getting errors:

qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""

export QT_QPA_PLATFORM=wayland gets me:

qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimal, xcb.

[1]    250800 IOT instruction (core dumped)  DISPLAY=:1 ~/bitcoin/bitcoin-31.1/bin/bitcoin-qt

ldd ~/bitcoin/bitcoin-31.1/bin/bitcoin-qt
        linux-vdso.so.1 (0x00007ae8816e3000)
        libfontconfig.so.1 => /usr/lib/x86_64-linux-gnu/libfontconfig.so.1 (0x00007ae881660000)
        libfreetype.so.6 => /usr/lib/x86_64-linux-gnu/libfreetype.so.6 (0x00007ae87eb2b000)
        libdl.so.2 => /usr/lib/x86_64-linux-gnu/libdl.so.2 (0x00007ae88165b000)
        libpthread.so.0 => /usr/lib/x86_64-linux-gnu/libpthread.so.0 (0x00007ae881656000)
        libm.so.6 => /usr/lib/x86_64-linux-gnu/libm.so.6 (0x00007ae87ea05000)
        libc.so.6 => /usr/lib/x86_64-linux-gnu/libc.so.6 (0x00007ae87e600000)
        /lib64/ld-linux-x86-64.so.2 (0x00007ae8816e5000)
        libexpat.so.1 => /usr/lib/x86_64-linux-gnu/libexpat.so.1 (0x00007ae881626000)
        libz.so.1 => /usr/lib/x86_64-linux-gnu/libz.so.1 (0x00007ae881608000)
        libbz2.so.1.0 => /usr/lib/x86_64-linux-gnu/libbz2.so.1.0 (0x00007ae8815f3000)
        libpng16.so.16 => /usr/lib/x86_64-linux-gnu/libpng16.so.16 (0x00007ae87e9cb000)
        libbrotlidec.so.1 => /usr/lib/x86_64-linux-gnu/libbrotlidec.so.1 (0x00007ae8815e4000)
        libbrotlicommon.so.1 => /usr/lib/x86_64-linux-gnu/libbrotlicommon.so.1 (0x00007ae87e9a8000)

bitcoind runs just fine

This is expected with the release binaries. bitcoin-qt from https://bitcoincore.org/ is built against a static Qt that includes only the xcb (X11) and minimal platform plugins, as your error output shows. There is no native Wayland plugin, so forcing QT_QPA_PLATFORM=wayland will always abort. Adding Wayland support to the release builds is tracked in bitcoin/bitcoin#19950.

As a workaround, try forcing the X11 backend (via XWayland):

$ QT_QPA_PLATFORM=xcb ~/bitcoin/bitcoin-31.1/bin/bitcoin-qt

If it still fails with the xcb plugin, please re-run with plugin debugging and post the output:

$ QT_DEBUG_PLUGINS=1 QT_QPA_PLATFORM=xcb ~/bitcoin/bitcoin-31.1/bin/bitcoin-qt

A common cause of such failures is a missing XCB runtime library. For example, Qt 6's xcb plugin needs libxcb-cursor0. Installing it may fix this:

$ sudo apt install libxcb-cursor0

If you want native Wayland now, you can build bitcoin-qt from source.

I ended up building the binaries myself thanks for the instructions at https://github.com/bitcoin/bitcoin/blob/master/doc/build-unix.md (none of the options above worked for me).

Nit: I noticed that bitcoin/bitcoin repo has tags and releases while this one here doesn't so I ended up building the former. Not sure what's the difference but it'd be worth making it known to users.