KDE dynamic high-dpi text scaling

I am looking for an equivalent of the following gnome setup, in KDE: Under **gnome+X11**, I can get instant scaling of gnome apps, KDE apps and chrome/chromium (>v49) when plugging my high-dpi monitor (27" 4K) by running: gsettings set org.gnome.desktop.interface text-scaling-factor 1.4 Note that (in a neophyte's words) this is not doing framebuffer-level scaling (that would be gnome's scaling-factor), it' only telling the toolkits to use bigger fonts (images are not affected). This gets picked-up **instantly** by gnome, qt, chrome. Other aps, like Intellij IDEs or Firefox need a restart (for Firefox I could script in a change of layout.css.devPixelsPerPx). On the other hand, in **KDE**, both Plasma "*Displays - Scale Display*" and "*Fonts - Force fonts DPI*" settings require a restart of all apps **including the same KDE apps which autodetected the gnome scaling change**!! This may be due to the KDE-GTK theme picking up the gnome setting, but still, it means Qt *can* redraw the interface in response to the change. Am I overlooking something? Can I modify the same low-level setting underlying the gnome one, from KDE? Is there something that can be improved in KDE code to improve the situation? I ran through [Arch](https://wiki.archlinux.org/index.php/HiDPI) and [Debian](https://wiki.debian.org/MonitorDPI) doc without success.