Removing the watermark/shadow of the palette title in Beamer

I would like to remove the title watermark/shadow from the title palette on the first page and the last page of Beamer. Can anybody help me?

\documentclass[10pt, a4paper, serif]{beamer}

\usetheme{Warsaw}

\title[November 2019]{Removing the watermark}
\subtitle[]{}
\author[Alexandre Loures]{Alexandre Loures}
\date{November 2019}

\begin{document}

\maketitle

\section{Removing the watermark}

\begin{frame}

\frametitle{}{}

Removing the watermark

\end{frame}

\include{help-thanks}

\end{document}


Being the thanks.tex:

\section{}

\begin{frame}

\centering
Thanks!

\end{frame}


Whose result is as follow:

I would like to remove the title shadow from the title palette on the first page and the last page of Beamer as follows:

• Please clarify where exactly you would like to remove teh shadow. In your question, you write " on the first page and the last page", on the screenshots, however, there are red arrows on all slides. – leandriis Nov 17 '19 at 9:31
• Hello @leandriis! It is only on the first and last page. I put a red arrow on all of them to demonstrate that I want the middle page to continue showing the section title. – Alexandre Loures Nov 17 '19 at 15:24
• So, do you want to only remove the shadow underneath the black/blue line or do you also want to remove the black/blue lines itself on the first and last slide? What should happen to the text on that line? Also remove it? Please clarify. – leandriis Nov 17 '19 at 19:06
• Having had a closer look at the screensots you posted, it seems as if you just wanted to remove the section title in the black header bar. Is that correct? – leandriis Nov 17 '19 at 19:07
• Hi @leandriis! That's right! I just want to remove the section title from the black header bar. The black / blue bars should remain. – Alexandre Loures Nov 24 '19 at 13:11

You can locally redefine the templates used, see for more examples this Q&A: Headlines in Beamer.

For your case this should do:

\documentclass[10pt, a4paper,serif]{beamer}
\usetheme{Warsaw}

\title[November 2019]{Title: Removing the watermark}
\author[Alexandre Loures]{Alexandre Loures}
\date{November 2019}

\begin{document}

\begingroup
\begin{frame}
\maketitle
\end{frame}
\endgroup

\section{Section: Removing the watermark}
\begin{frame}
Normal text: Removing the watermark
\end{frame}

% etc.
\end{document}


For more frequent uses I'd recommend defining a new environment:

\documentclass[10pt,a4paper,serif]{beamer}
\usetheme{Warsaw}

\title[November 2019]{Title: Removing the watermark}
\author[Alexandre Loures]{Alexandre Loures}
\date{November 2019}

{%
\begingroup
\begin{frame}
}{%
\end{frame}
\endgroup
}

\begin{document}

\maketitle

\section{Section: Removing the watermark}
\begin{frame}
Normal text: Removing the watermark
\end{frame}

% etc.
\end{document}

• Thank you! Setting a new environment worked very well for me! – Alexandre Loures Nov 24 '19 at 13:16

Probably you are satisfied with the newly defined \hidesectiontitles command as shown in the following MWE. If you want to use it on the title frame, make sure, you enclose both commands in a set of {}:

\documentclass[10pt, a4paper]{beamer}

\usetheme{Warsaw}

\usefonttheme{serif}

\title[November 2019]{Removing the watermark}
\subtitle[]{}
\author[Alexandre Loures]{Alexandre Loures}
\date{November 2019}

\begin{document}

{\hidesectiontitles
\maketitle}

\section{Removing the watermark}
\begin{frame}
\frametitle{}{}
Removing the watermark
\end{frame}

\hidesectiontitles
\begin{frame}
\centering
Thanks!
\end{frame}

\end{document}


Probably not the most elegant solution, but with redefining \pgfdeclareverticalshading as shown in the following example, you can remove the shadow under the frametitle on all frames of your presentation.

\documentclass[10pt, a4paper]{beamer}

\usetheme{Warsaw}

\AtBeginDocument{
color(0pt)=(bg);
color(0pt)=(bg)}
}

\usefonttheme{serif}

\title[November 2019]{Removing the watermark}
\subtitle[]{}
\author[Alexandre Loures]{Alexandre Loures}
\date{November 2019}

\begin{document}

\maketitle

\section{Removing the watermark}

\begin{frame}
\frametitle{}{}
Removing the watermark
\end{frame}

\section{}

\begin{frame}
\centering
Thanks!
\end{frame}

\end{document}