How to remove the words 'Who?' and 'When?' in the title page of Bergen beamer theme?

Question

I am creating a simple presentation using the Bergen theme in beamer. I like almost everything about it, except the words 'Who?' and 'When' as respective quantifiers for the author and date in the titlepage. How do I remove them?

The above being my first and foremost question, I have another request to the kind-hearted persons out here. Is it possible in a simple manner to embed the section headings in the sidebar in this theme, and to highlight the appropriate one while presenting? Much like the behaviour in the Berkeley theme?

The second one is only an added request. I really need to remove those two words from the titlepage. Please help. Following is an MWE:

\documentclass[aspectratio=169]{beamer}
\usetheme{Bergen}
\usefonttheme{serif}
\usecolortheme{wolverine}
\author[]{Subhajit Paul}
\title{Report of Even Semester, 2020-21}
\subtitle{Salesian College, Siliguri Campus}
\date{\today}
\begin{document}
    \begin{frame}
        \titlepage
    \end{frame}
\end{document}

Answer 1

To remove 'Who' and 'When', add the following in the preamble

\def\insertauthorindicator{}% Default is "Who?"
\def\insertdateindicator{}% Default is "When?"

For the second part, add the following to the preamble

\useoutertheme[left]{sidebar}