ssr bug in dev when using prerender

[dadamssg]

I'm using React Router as a...

framework

Reproduction

Clone the completed address-book tutorial here: https://github.com/dadamssg/address-book

System Info

System:
    OS: macOS 15.2
    CPU: (10) arm64 Apple M1 Max
    Memory: 449.53 MB / 64.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.18.2 - ~/.volta/tools/image/node/20.18.2/bin/node
    Yarn: 1.22.19 - ~/.volta/tools/image/yarn/1.22.19/bin/yarn
    npm: 10.8.2 - ~/.volta/tools/image/node/20.18.2/bin/npm
    pnpm: 9.9.0 - ~/Library/pnpm/pnpm
    bun: 1.1.38 - ~/.bun/bin/bun
  Browsers:
    Brave Browser: 129.1.70.117
    Chrome: 132.0.6834.160
    Safari: 18.2
  npmPackages:
    @react-router/dev: ^7.1.4 => 7.1.4 
    @react-router/node: ^7.1.4 => 7.1.4 
    @react-router/serve: ^7.1.4 => 7.1.4 
    react-router: ^7.1.4 => 7.1.4 
    vite: ^5.4.11 => 5.4.14

Used Package Manager

npm

Expected Behavior

I expect flipping the ssr true flag to have an effect. This seems to only happen when a prerender array is also defined even though it's not relevant to the current route.

Actual Behavior

If you start with ssr: true, changing it should have an effect. Video of issue here: https://youtu.be/epqpC3KmMM0

rr-ssr.480.mov

I'm using actions/loaders so it should immediately blow up when ssr is toggled off. I have to restart the dev server for the change to actually take affect.

[brophdawg11]

This should be resolved by #12948 and available in the next release.

The dev server should now error if it finds a loader in a non-pre-rendered route with ssr:false without requiring a server restart. It does require a browser reload to trigger the error at the moment.