diff --git a/build/PPA.txt b/build/PPA.txt
index 1d71b97..494a713 100644
--- a/build/PPA.txt
+++ b/build/PPA.txt
@@ -6,26 +6,52 @@ stable](https://launchpad.net/~swi-prolog/+archive/stable) and
 development](https://launchpad.net/~swi-prolog/+archive/devel) based on
 the official Debian packaging structure and corresponding SWI-Prolog
 release. This PPA version can be installed using the commands below in
-recent Ubuntu versions.
+Ubuntu linux.  The ``.deb`` package may run on some closely related
+Linux distributions.  Otherwise either use the (often outdated) package
+from our distribution, [compile from source](</build/>) or using the [SNAP](<snap.html>)
+version.
 
-These PPAs are updated with every new release.  Thanks to Yves Raimond for setting up the PPA snd Eugeniy Meshcheryakov for creating the Debian configuration.  The PPA is registered using `apt-add-repository`, which is by default available on desktops, but not on servers or Linux containers.  It is installed using:
+These PPAs are updated with every new release. Thanks to Yves Raimond
+for setting up the PPA snd Eugeniy Meshcheryakov for creating the Debian
+configuration. The PPA is registered using `apt-add-repository`, which
+is by default available on desktops, but not on servers or Linux
+containers. It is installed using:
 
-  ==
-  % sudo apt-get install software-properties-common
-  ==
+    % sudo apt-get install software-properties-common
 
----+++ Stable versions
+## Stable versions
 
-  ==
-  % sudo apt-add-repository ppa:swi-prolog/stable
-  % sudo apt-get update
-  % sudo apt-get install swi-prolog
-  ==
+    % sudo apt-add-repository ppa:swi-prolog/stable
+    % sudo apt-get update
+    % sudo apt-get install swi-prolog
 
----+++ Development versions
+## Development versions
 
-  ==
-  % sudo apt-add-repository ppa:swi-prolog/devel
-  % sudo apt-get update
-  % sudo apt-get install swi-prolog
-  ==
+    % sudo apt-add-repository ppa:swi-prolog/devel
+    % sudo apt-get update
+    % sudo apt-get install swi-prolog
+
+## Installing debug symbols
+
+If Prolog crashes and notably for debugging crashes when you embed
+SWI-Prolog or add foreign extensions, it is useful to have the _debug
+symbols_. Please install the debug symbols if you encounter a
+reproducible crash and include the stack trace in the bug report.
+
+
+As of versions 8.4.3/8.5.13 these are available. To install these, edit
+``/etc/apt/sources.list.d/swi-prolog-ubuntu-<version>.list``, duplicate
+the `deb` line and add ``/debug``. The file now may look like this (for
+the _stable_ version on Ubuntu 22.04 (jammy)).
+
+```
+deb https://ppa.launchpadcontent.net/swi-prolog/stable/ubuntu/ jammy main
+deb https://ppa.launchpadcontent.net/swi-prolog/stable/ubuntu/ jammy main/debug
+```
+
+Next, run these commands to get the debug symbols of the core Prolog
+system. The ``-dbgsym` packages are also available for the various
+additional packages.
+
+    % sudo apt update
+    % sudo apt install swi-prolog-nox-dbgsym