Deleting and Clearing Your Timeline Cache (iOS and macOS)
There can be times when Twitterrific performs sluggishly or you experience a re-draw error when scrolling in the timeline. When this happens it can sometimes help to clear the app's timeline cache from memory and start scratch. If this becomes necessary, here are the steps to clear the timeline cache on both iOS and macOS.
Tap and hold your round avatar at the upper left of the timeline to open the Account Picker. Next, tap & hold on the account you wish to clear the timeline cache for until it starts to wiggle. You'll also see a red X icon over the icon. Tap that and then select Clear Cache from the actions presented. The timeline will then reset itself and performance should improve.
Press CMD-, to open the Preferences panel and then select the Accounts tab. Select the account you wish to clear the cache for from the list provided and simply press the Clear Cache button.