How to replace a font in /System/Library/Fonts/Supplemental/ with a newer version?

[HandyMac]

In macOS Big Sur 11.7.10 I want to replace the NotoSansBrahmi-Regular.ttf font (v.2.000, 2020) which is in /System/Library/Fonts/Supplemental/ with the current version of that font, NotoSansBrahmi-Regular.ttf font (v.2.004, 2024), which has been improved. The old font cannot be deleted from that folder, either by dragging or by ⌘-delete. Nor can the newer version be dragged into the folder to replace the old version. I tried disabling System Integrity Protection, but that didn't help; the folder contents are still impervious to change. Does anyone know a way to do this?

 

[bogdanw]

Have you tried to install the new font and disable the old one?
Install and validate fonts in Font Book on Mac
https://support.apple.com/en-afri/guide/font-book/fntbk1000/10.0/mac/11.0
Remove, disable, or enable fonts in Font Book on Mac
https://support.apple.com/en-afri/guide/font-book/fntb2bcb512d/10.0/mac/11.0

 

[benwiggy]

You can't. The System volume is read-only, and is "signed and sealed". If the Mac detects that the OS has been modified, it may refuse to boot.

In addition, Apple has removed the ability to disable "Supplemental" system fonts.

Apple currently installs over 700 fonts that we can't disable. You can try putting your updated version in one of the other font folders, either /Library/Fonts or ~/Library/Fonts ; but you'll have two versions of the font installed, which is never a good idea.

(Sequoia doesn't have the new version, either.)

Send feedback to Apple pointing out the problem, and requesting that we have more control over system fonts.

What improvements does the new version have?