Error: Debug Failure. Unhandled class member kind! 33587200

[saschanaz]

TypeScript Version: 4.0.2

Search Terms: unhandled class member

Steps

1. Clone https://github.com/w3c/webidl2.js/tree/aa38fd7b922849552e5b8f199fcf9d39cc84b5fd
2. Run npm i && npx tsc --declaration --allowJs --outDir types --emitDeclarationOnly on the directory

Expected behavior: No error

Actual behavior:

> npx tsc --declaration --allowJs --outDir types --emitDeclarationOnly
C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:84772
                throw e;
                ^

Error: Debug Failure. Unhandled class member kind! 33587200
    at serializePropertySymbol (C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39601:41)
    at serializePropertySymbolForInterface (C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39605:28)
    at C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39284:104
    at Object.flatMap (C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:426:25)
    at serializeInterface (C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39284:38)
    at serializeSymbolWorker (C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39204:25)
    at serializeSymbol (C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39121:38)
    at C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39102:25
    at Map.forEach (<anonymous>)
    at visitSymbolTable (C:\Users\Kagami\Documents\GitHub\webidl2.js\node_modules\typescript\lib\tsc.js:39101:33)