Designer puppet keeps crashing at startup in batch renderer

The puppet keeps crashing at startup in qsgbatchrenderer::uploadBatch for nullptr error. This is a regression due to fix for https://bugreports.qt.io/browse/QTBUG-93956. The fix added shink(0) calls for vertex and index upload pools, but shink only deallocates the buffer and sets the capacity to 0, but doesn't update the size. When these pools then are used again they do not reallocate the buffers, because the size is non-zero.