This article explains how to disable GNOME’s overlay scrollbars so that the scrollbars are always visible.
GNOME / GTK applications use overlay scrollbars by default to maximize screen space. For most applications (with some exceptions, such as the GNOME Terminal’s scrollbar is permanently visible), the scrollbar is hidden by default, partially displayed when the pointer moves, and only fully visible when the mouse is placed near the scrollbar .

GNOME 3.34 , Released on Thursday with a new hidden content Option This makes it easy to always display the full scroll bar. Open the Dconf editor and navigate to org / gnome / desktop / interface And set overlay-scrolling to false Make the scrollbar visible.
You can use the following command to achieve the same purpose:

                      
                        gsettings set org.gnome.desktop.interface overlay-scrolling false
                      
                    

You need to restart each GTK3 application you have run so that it uses a permanently visible scroll bar. Or restart the session (logout / login).
Do you want to undo this change and use the default GNOME / GTK scrollbar behavior? Use any of the Dconf editors already explained, but set it up overlay-scrolling to true (Or default), or use the following command:

                      
                        gsettings set org.gnome.desktop.interface overlay-scrolling true
                      
                    

You might also like: How to completely disable Tracker, GNOME’s file indexing and search tools

Disable GNOME / GTK overlay scrollbar for GNOME versions earlier than 3.34

To disable overlay scrollbars and have permanently visible scrollbars on GNOME versions earlier than 3.34, you can use GTK_OVERLAY_SCROLLING=0 Environment variable.
Use it on each application like this (launch gedit In this example, make sure that the application is not running, otherwise it will not work):

                      
                        GTK_OVERLAY_SCROLLING=0 gedit
                      
                    

To apply it to all applications and disable GNOME’s overlay scrollbar on versions earlier than 3.34, add the following at your end ~/.profile file:

                      
                        export GTK_OVERLAY_SCROLLING=0
gdbus call --session --dest org.freedesktop.DBus --object-path /org/freedesktop/DBus --method org.freedesktop.DBus.UpdateActivationEnvironment '{"GTK_OVERLAY_SCROLLING": "0"}'
                      
                    

After saving this file, log out and log back in to see the actual changes.
Due to this Adjustment Published by dddevo on Reddit, all GTK3 applications have disabled overlay scrollbars, even those launched via D-Bus.
Use ~/.profile Only for your users. To apply system-wide, add it to /etc/profile.local Or in the following files /etc/profile.d/ (As root).

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