remove "Manuscript submitted to ACM"

The acmart class has the text Manuscript submitted to ACM explicitly hard-coded in standardpagestyle and firstpagestyle, so either one has to redefine those pagestyles (this will be tedious!) or applies a small patch with \ps@firstpagestyle etc., substituting the undesired text with empty space, which is done by \xpatchcmd and leaving the replacement 'slot' {} empty (see below)

In addition, if the document class option manuscript is set, the boolean 'variable' \@ACM@manuscript is set to true, so this should be set to false explicitly.

Small info: page styles are defined in a macro name \ps@X, where X stands for the name of the page style, i.e. plain or firstpagestyle.

Since @ macros are involved, a \makeatletter...\makeatother pair is needed.

\documentclass[review=true, screen, anonymous,manuscript]{acmart}

\usepackage{blindtext}

\usepackage{xpatch}

\makeatletter
\xpatchcmd{\ps@firstpagestyle}{Manuscript submitted to ACM}{}{\typeout{First patch succeeded}}{\typeout{first patch failed}}
\xpatchcmd{\ps@standardpagestyle}{Manuscript submitted to ACM}{}{\typeout{Second patch succeeded}}{\typeout{Second patch failed}}    \@ACM@manuscriptfalse% Also in titlepage
\makeatother

\settopmatter{printacmref=false} % Removes citation information below abstract
\renewcommand\footnotetextcopyrightpermission[1]{} % removes footnote with conference info
\setcopyright{none}
\pagestyle{plain} % remove running headers
\title{TBD}
\author{}
\begin{document}
\maketitle

\blindtext[20]
\end{document}

Just ran into this problem with the new ACM template and tried (unsuccessfully) a number of possible solutions. Then ran across this solution while carefully reading the class documentation.

Pass the nonacm option to the \documentclass command. See Table 2 in the acmart class documentation.

Example:

\documentclass[manuscript,screen,timestamp,authordraft,nonacm]{acmart}
                                                       ^^^^^^