diff --git a/cmd-parse.y b/cmd-parse.y
index 1d692770..cdf026f3 100644
--- a/cmd-parse.y
+++ b/cmd-parse.y
@@ -1086,7 +1086,8 @@ cmd_parse_from_arguments(struct args_value *values, u_int count,
 				arg->type = CMD_PARSE_STRING;
 				arg->string = copy;
 				TAILQ_INSERT_TAIL(&cmd->arguments, arg, entry);
-			}
+			} else
+				free(copy);
 		} else if (values[i].type == ARGS_COMMANDS) {
 			arg = xcalloc(1, sizeof *arg);
 			arg->type = CMD_PARSE_PARSED_COMMANDS;
diff --git a/screen-write.c b/screen-write.c
index 476fe4dd..a2107f2a 100644
--- a/screen-write.c
+++ b/screen-write.c
@@ -1505,8 +1505,10 @@ screen_write_fullredraw(struct screen_write_ctx *ctx)
 
 	screen_write_collect_flush(ctx, 0, __func__);
 
-	screen_write_initctx(ctx, &ttyctx, 1);
-	ttyctx.redraw_cb(&ttyctx);
+	if (ttyctx.redraw_cb != NULL) {
+		screen_write_initctx(ctx, &ttyctx, 1);
+		ttyctx.redraw_cb(&ttyctx);
+	}
 }
 
 /* Trim collected items. */
@@ -2127,8 +2129,10 @@ screen_write_alternateon(struct screen_write_ctx *ctx, struct grid_cell *gc,
 	screen_write_collect_flush(ctx, 0, __func__);
 	screen_alternate_on(ctx->s, gc, cursor);
 
-	screen_write_initctx(ctx, &ttyctx, 1);
-	ttyctx.redraw_cb(&ttyctx);
+	if (ttyctx.redraw_cb != NULL) {
+		screen_write_initctx(ctx, &ttyctx, 1);
+		ttyctx.redraw_cb(&ttyctx);
+	}
 }
 
 /* Turn alternate screen off. */
@@ -2145,6 +2149,8 @@ screen_write_alternateoff(struct screen_write_ctx *ctx, struct grid_cell *gc,
 	screen_write_collect_flush(ctx, 0, __func__);
 	screen_alternate_off(ctx->s, gc, cursor);
 
-	screen_write_initctx(ctx, &ttyctx, 1);
-	ttyctx.redraw_cb(&ttyctx);
+	if (ttyctx.redraw_cb != NULL) {
+		screen_write_initctx(ctx, &ttyctx, 1);
+		ttyctx.redraw_cb(&ttyctx);
+	}
 }