Which @angular/* package(s) are the source of the bug?

Don't known / other

Is this a regression?

No

Description

I'm experiencing an issue where a computed expression does not consistently update when its signal dependency is updated via the .update() method (it works when using .set() instead.) Specifically, in this case it updates the first time .update() is invoked, but not any sequential time.

I've verified that the signal dependency is indeed getting updated via Angular Dev Tools and console.log() invocations.

Please provide a link to a minimal reproduction of the bug

https://stackblitz.com/edit/stackblitz-starters-uiyfuqpe?file=src%2Fmain.ts

Please provide the exception or error you saw

The computed expression does not update after the first update of its signal dependency.

Please provide the environment you discovered this bug in (run ng version)

Angular CLI: 20.0.1
Node: 24.1.0
Package Manager: npm 11.3.0
OS: linux x64

Angular: 20.0.2
... common, compiler, compiler-cli, core, forms
... platform-browser, router

Package                      Version
------------------------------------------------------
@angular-devkit/architect    0.2000.1
@angular-devkit/core         20.0.1
@angular-devkit/schematics   20.0.1
@angular/build               20.0.1
@angular/cli                 20.0.1
@schematics/angular          20.0.1
rxjs                         7.8.2
typescript                   5.8.3
zone.js                      0.15.1

Anything else?

Thanks for all your hard work and contributions to open source!