If Thunderbird is not displaying clickable hyperlinks, you can try the following troubleshooting steps:

Check HTML message format: Ensure that the email you're viewing is in HTML format and not plain text. Thunderbird may not display clickable hyperlinks in plain text mode. You can switch between HTML and plain text views by going to the "View" menu and selecting "Message Body As" > "Original HTML" or "Simple HTML."

Verify Thunderbird settings: Check your Thunderbird settings to make sure hyperlinks are enabled. To do this, go to Thunderbird's main menu, select "Tools," and choose "Options" (or "Preferences" on macOS). In the Options/Preferences window, select the "Display" tab and make sure the "Allow remote content in messages" option is checked. This allows Thunderbird to display hyperlinks correctly.

Disable add-ons or extensions: Certain add-ons or extensions in Thunderbird can interfere with the display of hyperlinks. Try disabling any add-ons or extensions you have installed and see if the issue persists. To disable add-ons, go to the main menu, select "Tools," and choose "Add-ons." Disable any extensions and restart Thunderbird.

Update Thunderbird: Make sure you have the latest version of Thunderbird installed. Outdated versions may have bugs or compatibility issues that could affect the display of hyperlinks. You can check for updates by going to the main menu, selecting "Help," and choosing "About Thunderbird." If an update is available, follow the prompts to install it.

Check antivirus or firewall settings: Some antivirus programs or firewall settings can interfere with Thunderbird's ability to display hyperlinks. Temporarily disable any antivirus software or adjust firewall settings and see if that resolves the issue.

I have this problem and I believe I have covered all the above suggestions. Wandered around settings. No help.

TB version:

115.1.1 (64-bit) Release notes

Using Brave.

Brave is up to date Version 1.57.47 Chromium: 116.0.5845.96 (Official Build) (64-bit)

Windows 10