Since WordPress 5.4 you get a new feature called ‘Fullscreen mode’. This feature allows you to work on your content without any distractions. However, most of us are used to with accessing the navigation menu while writing content. There are multiple ways how you can disable the fullscreen mode.
Disable using option provided by WordPress
While you are on edit post or edit page screen, look at the top right side. You will notice three dots.
Navigate to post/page edit screen
Open the post or page edit screen by clicking on any post or page from the post/page listing screen.
Locate three dots on top right
Once you are on post/page edit screen, look top right. You will notice three dots. Hovering on it would show a tooltip called “More tools & options”.
Toggle the “Fullscreen mode” option
Click on those three dots and you will see a menu in the dropdown that reads “Fullscreen mode”. Click on that and you will see the left sidebar back in place.
The above setting is saved at browser level. Thus, if you use different browser or different device then you will need to toggle this setting again. Then what is a permanent solution for this? Read through…
Disable using a plugin
The plugin “Disable Block Editor FullScreen mode” allows you to disable the fullscreen mode for the entire site.
Thus irrespective of which browser you are using or which device you are using the plugin will forcefully disable the fullscreen mode. However, user can always toggle the behaviour using the option provided under “More tools & options” menu on the top right.