diff --git a/Help/gc_basicsettings.html b/Help/gc_basicsettings.html
index 914f5d3..cf6beed 100644
--- a/Help/gc_basicsettings.html
+++ b/Help/gc_basicsettings.html
@@ -151,8 +151,8 @@ defaultskytextures
 	Default value is <b>false</b>.<br />
 	<br />
     <b class="fat">sidedefcompressionignoresaction</b> (boolean) - <span class="red">GZDB only</span>.<br />
-    When set to true, sidedefs will be compressed regardless of linedef action (DB2 behaviour, can potentially cause problems when target source port doesn't decompress sidedefs).<br />
-    When set to false, sidedefs, which belong to a line with an action, will be skipped when compressing sidedefs.<br />
+    When set to true, sidedefs will be compressed regardless of linedef action or tag(s) (DB2 behaviour, can potentially cause problems when target source port doesn't decompress sidedefs).<br />
+    When set to false, sidedefs, which belong to a line with an action or non-zero tag(s), will be skipped when compressing sidedefs.<br />
     Default value is <b>false</b>.<br />
 	</p>
 	</div>
diff --git a/Source/Core/Map/MapSet.cs b/Source/Core/Map/MapSet.cs
index b1563ec..5d85289 100644
--- a/Source/Core/Map/MapSet.cs
+++ b/Source/Core/Map/MapSet.cs
@@ -3211,8 +3211,8 @@ namespace CodeImp.DoomBuilder.Map
 				Sidedef stored = null;
 				Sidedef snsd = sidedefs[sn];
 
-				//mxd. Skip sidedef if it belongs to a linedef with an action?
-				if(!General.Map.Config.SidedefCompressionIgnoresAction && snsd.Line.Action != 0)
+				//mxd. Skip sidedef if it belongs to a linedef with an action or tag?
+				if(!General.Map.Config.SidedefCompressionIgnoresAction && (snsd.Line.Action != 0 || snsd.Line.Tag != 0))
 				{
 					// Next!
 					sn++;