How do I show battery percentage in GNOME Panel without using any extension?
Solution 1:
Open dconf Editor and navigate to /org/gnome/desktop/interface/show-battery-percentage. Then disable "Use default value" and select True in the "Custom value" field.
Alternatively just open Terminal and run
gsettings set org.gnome.desktop.interface show-battery-percentage true
Same settings can be found in (GNOME) Tweaks under Top Bar:
