Index: CONTRIBUTING
==================================================================
--- CONTRIBUTING
+++ CONTRIBUTING
@@ -86,13 +86,12 @@
 
 
 === Bug reports ===
 
 To make a bug report, the recommended way is to post a message on the NNTP,
-but you may also use IRC, Matrix, or the GitHub issues. Before posting a
-bug report, read the following list and provide as much of these things as
-is possible:
+but you may also use IRC or the GitHub issues. Before posting a bug report,
+read the following list and provide as much of these things as is possible:
 
 * Check if the bug has already been reported/known. (If you have further
 comments about an existing report, you can post a follow-up message.)
 
 * Use a clear title and description.
@@ -132,13 +131,12 @@
 
 
 === Feature requests ===
 
 To make a feature request, the recommended way is to post a message on the
-NNTP, but you may also use IRC, Matrix, or the GitHub issues. Before
-posting, read the following, and provide as much of the following as
-is possible:
+NNTP, but you may also use IRC or the GitHub issues. Before posting, read
+the following, and provide as much of the following as is possible:
 
 * Check if there is already a similar request. (If you have further
 comments about an existing report, you can post a follow-up message.)
 
 * Use a clear title and description.

Index: README
==================================================================
--- README
+++ README
@@ -246,16 +246,15 @@
 There is also the IRC channel #freeheromesh on Libera. Logs of this IRC
 are available at:
 
   https://logs.esolangs.org/libera-freeheromesh/
 
-There is also a Matrix chat, which is linked with the IRC. It is:
-
-  https://matrix.to/#/#freeheromesh:libera.chat
-
-(Note: I have not tried the Matrix chat and I do not know if it works.)
+(There was previously a Matrix chat as well, but Libera has removed the
+Matrix chat for now. If someone else who uses Matrix sets up a plumbed
+Matrix chat to connect to the IRC (please contact me for details), then
+I will mention that here.)
 
 
 === License ===
 
 Free Hero Mesh is public domain. See the LICENSE file for details.
 

Index: TODO
==================================================================
--- TODO
+++ TODO
@@ -64,5 +64,6 @@
   * PuzzleScript (limited; not everything is or will be capable)
   * Sokoban
   * Puzzle Boy
   * Pitman/Catrap
 * Improve build system
+  * Use C instead of JavaScript for auto-generated files