(@rollup/plugin-typescript) Cannot import typescript file from parent folder (../script) without .ts file extension (../script.ts)

[danielFHcode]

• Rollup Plugin Name: @rollup/plugin-typescript
• Rollup Plugin Version: 11.1.6
• Rollup Version: 4.13.2
• Operating System (or Browser): Browser (Stackblitz)
• Node Version: 18.18.0
• Link to reproduction: https://stackblitz.com/edit/stackblitz-webcontainer-api-starter-751pte?file=folder%2Fpackage.json,folder%2Frollup.config.js,script1.ts,folder%2Fscript2.ts

Expected Behavior

When bundling folder/script2.ts (from inside folder) rollup should be able to understand that import {helloWorld} from '../script1' refers to ../script1.ts, and bundle it with no errors.

Actual Behavior

I get this error:

[!] RollupError: Could not resolve "../script1" from "script2.ts"
script2.ts
    at getRollupError (/home/projects/stackblitz-webcontainer-api-starter-751pte/folder/node_modules/rollup/dist/shared/parseAst.js:282:41)
    at Object.error (/home/projects/stackblitz-webcontainer-api-starter-751pte/folder/node_modules/rollup/dist/shared/parseAst.js:278:42)
    at ModuleLoader.handleInvalidResolvedId (/home/projects/stackblitz-webcontainer-api-starter-751pte/folder/node_modules/rollup/dist/shared/rollup.js:20000:36)
    at eval (/home/projects/stackblitz-webcontainer-api-starter-751pte/folder/node_modules/rollup/dist/shared/rollup.js:19960:26)

Additional Information

This problem does not acre:

• When folder/script2.ts and script1.ts are in the same folder.
• When the project root (i.e. the package.json) is in / and not /folder.
• When using javascript files instead of typescript ones.
• When importing ../script1.ts instead of ../script1 or ../script1.js (though typescript's compiler is not happy about that, you have to enable allowImportingTsExtensions in the tsconfig)

For all of these reasons I believe that this is a bug and not an intended feature.