repro.sh

gh repo clone https://github.com/colinhacks/live-typescript-monorepo
cd live-typescript-monorepo
cd project-references
pnpm i
code .
# open packages/pkg-b/index.ts 
# see Cannot find module 'pkg-a' or its corresponding type declarations
pnpm build # runs `tsc -b`
# restart ts server, "Cannot find module" goes away
pnpm clean # deletes node_modules in all packages
# error returns