What Happens if You Clear Cache in the Facebook App?
How Do I Clear My Cache and Cookies on Facebook?
Clearing your cache from theFacebookapp itself is very straightforward and requires only a few steps.

Scroll down and tapSettings & privacy.
Scroll down to thePermissionssection and tapBrowser.
TapClearunderBrowsing Datato clear your apps cache.

Is It OK to Clear Data on Facebook?
It is completely okay to clear your Facebook cache.
Then, select thethree-dotmenu.
SelectRemove this notificationto delete that one.
Go toSettings>Notificationsto disable specific types of alerts (for example, “People You May Know.”
You candelete Facebook searchesboth in a web net surf tool and in the app.
In the app, select theSearchicon (magnifying glass) >Edit>Clear Searches.