QT for some reason messes with XCompose causing broken input (Qt 5 only - Qt 4 did not break anything). In Qt 5.2 and 5.3 this was causing an invalid conversion in chat messages containing these resulting in the bad bytes being stripped. In Qt 5.9 it is still broken, but you at least get a string with something in it. This checks for non-zero converted strings for room creation and chat lines.

cmake_minimum_required(VERSION 2.8.12)

project(qmlfrontend LANGUAGES CXX)

set(CMAKE_INCLUDE_CURRENT_DIR ON)
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTORCC ON)

find_package(Qt5 COMPONENTS Core Quick REQUIRED)

add_executable(${PROJECT_NAME} "main.cpp" "qml.qrc")

target_link_libraries(${PROJECT_NAME} Qt5::Core Qt5::Quick)