[CString.StripControls] Srip bg colours when we reset fg

test/StringTest.cpp

@@ -263,3 +263,11 @@ TEST(StringTest, Contains) {
     EXPECT_FALSE(
         CString("Hello, I'm Bob").Contains("i'm bob", CString::CaseSensitive));
 }
+
+TEST(StringTest, StripControls) {
+    // Strips reset colours
+    EXPECT_EQ(CString("\x03test").StripControls(), "test");
+
+    // Strips reset foreground and set new background colour
+    EXPECT_EQ(CString("\x03,03test").StripControls(), "test");
+}