Loading a startup page is not working properly

If one has a startup page and is shutting down the browser in a different mode than the mode used during startup then this page won't load during the next startup. It does not matter whether you shutdown your browser while being in Tor mode and starting the next time in Non-Tor mode or vice versa.

Reproducible: Always

Expected result: Loading the startup page should not depend on the state the browser was shut down the last time. I.e. it should always load when the browser starts up.