JupyterLab File>Save all issue in 3.6.3

Hello here, I recently updated jupyterlab version from 2.5.9 to 3.6.3. Something i’ve caught is that File>Save All is not working properly. I tried in my extension as well as native jupyterlab locally. i had multiple notebooks open with unsaved change, but “save all” button was never enabled. Is this a bug or am i doing something wrong?

jupyter server is 2.5.0, notebook 6.4.8