How to Fix Catalina Display Issue – Horizontal lines in application windows

Many MacBook Catalina users have reported the horizontal bars in the display while working on Google Chrome. The horizontal lines are blue, red, and green sometimes. The issue does not actively belong to the Apple environment because it occurs specifically only on Google Chrome. The problem was reported in Apple discussion by the user using MacOS Catalina 10.15.4. The issue is prone to occur due to altered GPU rending. We have researched the topic and listed a couple of ways to fix the very issue regarding the topic of how to fix the Catalina display issue – horizontal lines in application windows.

Solution 1: Disable Hardware Acceleration on Chrome

Step 1: Launch Google Chrome on your MacBook.

Step 2: Click on the “three-vertical menu” dots at the top-right corner.

Step 3: Now, click on “Settings.”

Step 4: After that, go to “Advanced” settings at the right panel of your screen.

Step 5: On the advance, click on more tab, then click on “System.”

Step 6: On the system settings, look towards the main page, there turn on “Use hardware and acceleration when available.” The browser will reopen and test for the potential issue and fix it.

Solution 2: Enable Metal [Solve Catalina Display Issue]

Enabling metal is the experimental feature that could possibly fix the display issue in Catalina.

Step 1: Launch Google Chrome on MacBook.

Step 2: Now, on the URL bar, type chrome://flags/ and then hit enter.

Step 3: On the available experimental window, type “Metal.”

Step 4: Now, click on the box at the right corner and select “Enabled.”

Step 5: Restart your Chrome browser, and look if the issue is resolved.

Solution 3: Update Chrome and MacBook

The versions of MacBook and unsupportable chrome browser could also cause the display issue- Horizontal blue lines in the application window.

Update macOS Catalina:

Step 1: Click on the Apple logo on the top-right corner.

Step 2: Now, click on “System Preferences.”

Step 3: After that, click on “Software Update” and begin the update.

Update Google Chrome:

Updating chrome to the latest version is helpful to solve issues regarding display and security risks. Follow the guidelines below.

Step 1: Initially open Google Chrome.

Step 2: Click on three vertical dots at the top-right corner.

Step 3: Now, click on “Help” and then to “About Google Chrome.”

Step 4: Now, on the main panel, you will see an update if available; click on the “Update” button to begin.

Solution 4: Reset NVRAM and SMC

Reset NVRAM

Step 1: Restart your MacBook from the lock screen.

Step 2: Now, as soon Mac opens, press and hold CMD + P + R key at once.

Step 3:  Finally, press and hold the keys until you see the Apple logo glowing on the screen.

PC will automatically boot normally now.

Reset SMC

Step 1: Restart your MacBook from the lock screen.

Step 2: Now, as soon Mac starts to lit, press and hold Shift + Option + Control + R key at once.

Step 3: Finally, press and hold the keys until you see the Apple logo glowing on the screen.

After successful steps, your PC should boot normally and solve issues regarding how to fix Catalina display issue – horizontal lines in application windows