bug(COMPONENT): Font Awesome Icons have styling problems when a mat-button is on the page

### Is this a regression?

- [x] Yes, this behavior used to work in the previous version

### The previous version in which this bug was not present was

19.2.8

### Description

Material buttons cause styling for mat-icon-buttons containing font awesome icons in safari and chrome

### Reproduction

StackBlitz link: https://stackblitz.com/edit/stackblitz-starters-ga6nsxqe?file=src%2Fmain.ts,angular.json,src%2Fglobal_styles.css
Steps to reproduce:
1. Clicking any of the red icon buttons will toggle a variable that controls whether the mat-button is in the DOM. To view the problem make sure the button is toggled visible.

### Expected Behavior

Icons will remain the same size and stay visible weather there is a material button in the DOM or not

### Actual Behavior

In Chrome: Some of the taller font awesome icons will be extra tall when a button is in the DOM and be the correct size when there are no buttons in the DOM. Forcing sizes with css classes or direct styles does not impact the height of the icon when the material button is in the DOM. Note that fa-building and fa-play are two examples of taller font awesome icons while fa-toolbox is normal size. In Chrome fa-toolbox behaves how it should when the material button is in the DOM.

Here is what it looks like when the button is toggled into the DOM in chrome:

Here is what it looks like when the button is toggled out of the DOM in chrome:

In Safari: All of the font awesome icons disappear entirely when the button is in the DOM

Here is what it looks like when the button is toggled into the DOM in safari:

Here is what it looks like when the button is toggled out of the DOM in safari

Note the fourth icon is visible in safari, this is a normal home icon from material icons and I included it for reference. The other three (fa-building, fa-play, and fa-toolbox) are all font awesome icons

### Environment

Angular CLI: 20.3.10
Node: 20.19.1
Package Manager: npm 10.8.2
OS: linux x64

Angular: 20.3.11
... animations, common, compiler, compiler-cli, core, forms
... platform-browser, router

Package Version
---------------------------------------
@angular-devkit/architect 0.2003.10
@angular-devkit/build-angular 20.3.10
@angular-devkit/core 20.3.10
@angular-devkit/schematics 20.3.10
@angular/cdk 20.2.13
@angular/cli 20.3.10
@angular/material 20.2.13
@schematics/angular 20.3.10
rxjs 7.8.2
typescript 5.8.3

Browsers: Chrome and Safari

Start with the linked StackBlitz reproduction, especially src/main.ts, angular.json, and src/global_styles.css. Toggle the mat-button in Chrome and Safari and compare the Font Awesome icons with the material home icon. Done means the icons keep their expected size and remain visible in both browsers whether the material button is present or not.

Written by the indexing model from the issue text.