Further document how do use the error overlays

doc/modules/ROOT/pages/usage/code_evaluation.adoc

@@ -189,7 +189,17 @@ variable.
 (setq cider-overlays-use-font-lock t)
 ----
 
-If you don't like seeing overlays so often,
+Overlays will be shown for errors,
+as long as they are not already displayed by `cider-stacktrace-mode`.
+In order to always favor error overlays over the `\*cider-error\*` buffer,
+please customize:
+
+[source,lisp]
+----
+(setq cider-show-error-buffer nil)
+----
+
+If you only want to see overlays for errors (and not for successful evaluations),
 you can restrict overlays to only be shown for errors
 (and display non-error results in the echo area at the bottom)
 by customizing the `cider-use-overlays` variable:
@@ -285,7 +295,7 @@ By default CIDER will display the output produced by some evaluation in the REPL
 (setq cider-interactive-eval-output-destination 'output-buffer)
 ----
 
-Additionally, there's the variable `cider-redirect-server-output-to-repl` that captures output that would normally end up in the `*nrepl-server*` buffer (provided it has been started via `cider-jack-in`) and redirects it to the REPL buffer. You can disable this redirection like this:
+Additionally, there's the variable `cider-redirect-server-output-to-repl` that captures output that would normally end up in the `\*nrepl-server\*` buffer (provided it has been started via `cider-jack-in`) and redirects it to the REPL buffer. You can disable this redirection like this:
 
 [source,lisp]
 ----