This disables 'auto-composition-mode' on frames that display on
terminals of this type.
+** Screen readers get confused about character position
+
+The Emacs display code sometimes emits TAB characters purely for motion
+on the terminal, even when those characters do not exist in the buffer.
+This can confuse screen reader software under certain terminal emulators
+(rxvt and vte have been cited). Switching to destructive tabs by running
+
+ stty -tabs
+
+in the terminal before starting Emacs may mitigate this. See also the
+discussion in Bug#78474 <https://debbugs.gnu.org/78474>.
+
* Runtime problems specific to individual Unix variants
** GNU/Linux