Slack Screen Flickering Mac Fix [Solved]

Immediate Fix

If your Slack interface is flickering, flashing black, or showing visual artifacts on macOS, the most effective solution is to toggle the Hardware Acceleration setting. This usually resolves conflicts between the Electron framework and the macOS GPU drivers.

Follow these steps to stop the flickering immediately:

1. Open the Slack application.
2. Click on your workspace name in the top-left corner and select Settings (or Preferences).
3. Navigate to the Advanced tab in the sidebar.
4. Locate the Hardware Acceleration section.
5. Uncheck the box labeled “Disable hardware acceleration”. If it is already unchecked, try checking it and restarting.
6. Click Restart Slack when prompted.

Technical Explanation

Slack is built using the Electron framework, which essentially runs a version of the Chromium browser to display the app. Screen flickering typically occurs when Chromium’s rendering engine clashes with the macOS Metal API or specific GPU drivers on M1/M2/M3 chips.

This behavior is frequently observed on MacBook Pro models with ProMotion (120Hz) displays. When the app attempts to sync its frame rate with the variable refresh rate of the monitor, a “buffer swap” error can occur, leading to the flickering effect you see on screen.

Alternative Methods

If disabling hardware acceleration did not resolve the issue, you may need to clear the application’s cache or adjust your display settings.

1. Clear Slack Cache via Terminal

Corrupted cache files can interfere with how the UI renders. You can force a deep clean of the Slack cache using the Terminal application:

rm -rf ~/Library/Application\ Support/Slack/Service\ Worker/CacheStorage/*
rm -rf ~/Library/Application\ Support/Slack/Cache/*

2. Adjust Display Refresh Rate

If you are using an external monitor or a ProMotion display, locking the refresh rate can stabilize the video output. Navigate to System Settings > Displays and change the Refresh Rate from “ProMotion” to a fixed 60 Hertz.

3. Comparison of Fixes