libxtst-dev binary package in Ubuntu Focal armhf

 libXtst provides an X Window System client interface to the Record
 extension to the X protocol.
 .
 The Record extension allows X clients to synthesise input events, which
 is useful for automated testing.
 .
 This package contains the development headers for the library found in
 libxtst6. Non-developers likely have little use for this package.
 .
 More information about X.Org can be found at:
 <URL:https://www.X.org>
 .
 This module can be found at
 git://anongit.freedesktop.org/git/xorg/lib/libXtst

Source package