Hello Abdul,
I had also changed this one into my favicon! I found out that the following url shows the favicon:
/sap/bc/ui5_ui5/ui2/ushell/resources/sap/ushell/themes/base/img/launchpad_favicon.ico.
I can not change the launchpad_favicon.ico with url /sap/bc/theming/themes/~client-420/UI5/sap/ushell/themes/base/img and I can not find aunchpad_favicon.ico in the MIME repository.
Kind Regards,
Richard