JupyterLab ToolbarButton Changeable Label

Hey everyone,

I have created a ToolbarButton via the ToolbarButton Class from @jupyterlab/apputils
ow I need to change the label of the button dynamically after it has been added to the Toolbar.

Unfortunately I get the error message Property 'props' is private and only accessible within class 'ToolbarButton'.
Is there a chance to change the label of the ToolbarButton afterwards and display the updated version instead of manipulating the raw HTML element?