You need to define a module for typescript to evaluate, otherwise it will try to look for something like toolbox.xml.ts
.
Something along these lines in a file called XML.d.ts (for this placed in a folder @types in src):
declare module "*.xml" {
const doc: any; // Change this to an actual XML type
export default doc;
}
and add "typeRoots": ["src/@types", "node_modules/@types"]
to your tsconfig.json (this makes typescript pick up the new typings file along with all installed types).