Svelte example doesn't work

When running either the svelte example from the cloned examples/ directory, or after generating a fresh svelte project, I am getting this error:

Uncaught Svelte error: component_api_invalid_new
Attempted to instantiate src/App.svelte with `new App`, which is no longer valid in Svelte 5. If this component is not under your control, set the `compatibility.componentApi` compiler option to `4` to keep it working.
https://svelte.dev/e/component_api_invalid_new

	in <unknown>
    component_api_invalid_new errors.js:103
    check_target legacy.js:8
    App App.svelte:17
    effect hmr.js:51
    update_reaction runtime.js:259
    update_effect runtime.js:468
    create_effect effects.js:138
    branch effects.js:432
    wrapper hmr.js:42
    update_reaction runtime.js:259
    update_effect runtime.js:468
    create_effect effects.js:138
    block effects.js:409
    wrapper hmr.js:31
    <anonymous> main.js:4
errors.js:103:17
    component_api_invalid_new errors.js:103
    check_target legacy.js:8
    App App.svelte:17
    effect hmr.js:51
    update_reaction runtime.js:259
    update_effect runtime.js:468
    create_effect effects.js:138
    branch effects.js:432
    wrapper hmr.js:42
    update_reaction runtime.js:259
    update_effect runtime.js:468
    create_effect effects.js:138
    block effects.js:409
    wrapper hmr.js:31
    <anonymous> main.js:4

(The screen is just white, and to get this error, I just opened the page in firefox)

Start by running the Svelte example from the examples/ directory and inspect the stack-trace locations in src/App.svelte and main.js. Compare the generated project with the example and verify that opening the page no longer produces component_api_invalid_new or a white screen.