Neon dev unstable here... search for "default applications" KCM in the apps launcher and open it. Click "File manager" section Window is too small as you can see in my screenshot.
Created attachment 115073 [details] screenshot
Not a QML KCM, so probably its sizeHint is too low.
It computes the sizeHint from the first (default) page. It would need to go through all pages and use QSize::expandedTo() with the sizeHint for each of them.
Git commit cf1305a2fb40b96d4b57041bafd57ef44d0534b0 by Nate Graham, on behalf of Tigran Gabrielyan. Committed on 30/03/2019 at 19:20. Pushed by ngraham into branch 'master'. Fix Default Applications KCM window size Summary: Config widgets were loading in when a service item was clicked. This change loads all config widgets at the start so the window can be sized to the largest widget. FIXED-IN: 5.16.0 Reviewers: #plasma, ngraham Reviewed By: ngraham Subscribers: ngraham, plasma-devel Tags: #plasma Differential Revision: https://phabricator.kde.org/D20072 M +36 -59 kcms/componentchooser/componentchooser.cpp M +4 -0 kcms/componentchooser/componentchooser.h https://commits.kde.org/plasma-desktop/cf1305a2fb40b96d4b57041bafd57ef44d0534b0