diff --git a/image-grid.c b/image-grid.c
index aadd64812..72a9e3272 100644
--- a/image-grid.c
+++ b/image-grid.c
@@ -206,41 +206,47 @@ image_grid_add(struct grid *gd, struct image *im, u_int x, u_int y,
 	}
 }
 
-/* Remove the covered part of a span. */
+/* Remove the covered part of one span. */
+static void
+image_span_remove(struct image_span *span, u_int x, u_int end)
+{
+	u_int	span_end = span->x + span->sx;
+
+	if (span_end <= x || span->x >= end)
+		return;
+	if (span->x < x && span_end > end) {
+		span->sx = x - span->x;
+		image_span_add(span->line, span->placement, end, span_end - end,
+		    span->source_x + end - span->x, span->source_y);
+		return;
+	}
+	if (span->x < x) {
+		span->sx = x - span->x;
+		return;
+	}
+	if (span_end > end) {
+		span->source_x += end - span->x;
+		span->sx = span_end - end;
+		span->x = end;
+		return;
+	}
+	image_span_free(span);
+}
+
+/* Remove a range of cells from every span on a line. */
 static void
 image_line_remove(struct image_line *line, u_int x, u_int w)
 {
 	struct image_span	*span, *next;
-	u_int			 end, span_end, right;
+	u_int			 end;
 
 	if (line == NULL || w == 0)
 		return;
 	end = x + w;
 	if (end < x)
 		end = UINT_MAX;
-	TAILQ_FOREACH_SAFE(span, &line->spans, line_entry, next) {
-		span_end = span->x + span->sx;
-		if (span_end <= x || span->x >= end)
-			continue;
-		if (span->x < x && span_end > end) {
-			right = span_end - end;
-			span->sx = x - span->x;
-			image_span_add(line, span->placement, end, right,
-			    span->source_x + end - span->x, span->source_y);
-			continue;
-		}
-		if (span->x < x) {
-			span->sx = x - span->x;
-			continue;
-		}
-		if (span_end > end) {
-			span->source_x += end - span->x;
-			span->sx = span_end - end;
-			span->x = end;
-			continue;
-		}
-		image_span_free(span);
-	}
+	TAILQ_FOREACH_SAFE(span, &line->spans, line_entry, next)
+		image_span_remove(span, x, end);
 }
 
 /* Remove a rectangle of image spans from a grid. */
@@ -542,13 +548,69 @@ image_cell_has_visible_pixels(struct image *im, u_int x, u_int y)
 	return (0);
 }
 
+/* Return whether a new cell's pixels completely cover an old cell. */
+static int
+image_cell_covers(struct image *new, u_int nx, u_int ny, struct image *old,
+    u_int ox, u_int oy)
+{
+	u_int		 npx, npy, nsx, nsy, opx, opy, osx, osy, xx, yy;
+	u_int		 ncw, nch, ocw, och, ncx, ncy, ocx, ocy;
+	const u_char	*np, *op, *npixels, *opixels;
+	size_t		 nstride, ostride;
+
+	image_get_canvas_size(new, &ncw, &nch);
+	image_get_canvas_size(old, &ocw, &och);
+	image_get_size_in_cells(new, &ncx, &ncy);
+	image_get_size_in_cells(old, &ocx, &ocy);
+	if (ncw / ncx != ocw / ocx || nch / ncy != och / ocy)
+		return (0);
+	image_get_pixel_area(new, nx, ny, 1, 1, &npx, &npy, &nsx, &nsy);
+	image_get_pixel_area(old, ox, oy, 1, 1, &opx, &opy, &osx, &osy);
+
+	npixels = image_get_pixels(new, &nstride, NULL);
+	opixels = image_get_pixels(old, &ostride, NULL);
+	for (yy = 0; yy < osy; yy++) {
+		op = opixels + (opy + yy) * ostride + opx * 4;
+		if (yy < nsy) {
+			np = npixels + (npy + yy) * nstride + npx * 4;
+		}
+		for (xx = 0; xx < osx; xx++) {
+			if (op[xx * 4 + 3] == 0)
+				continue;
+			if (yy >= nsy || xx >= nsx || np[xx * 4 + 3] != 255)
+				return (0);
+		}
+	}
+	return (1);
+}
+
+/* Discard cells of older placements fully covered by a new image. */
+static void
+image_line_cover(struct image_line *line, struct image_placement *plmt,
+    u_int x, u_int src_x, u_int src_y)
+{
+	struct image_span	*span, *next;
+	struct image_placement	*old;
+
+	TAILQ_FOREACH_SAFE(span, &line->spans, line_entry, next) {
+		old = span->placement;
+		if (old == plmt || x < span->x || x >= span->x + span->sx)
+			continue;
+		if (!image_cell_covers(plmt->image, src_x, src_y,
+		    old->image, span->source_x + x - span->x,
+		    span->source_y))
+			continue;
+		image_span_remove(span, x, x + 1);
+	}
+}
+
 /* Attach the visible runs from one image row. */
 static void
 image_add_row(struct image_line *line, struct image_placement *plmt,
     u_int cx, u_int src_y, u_int sx)
 {
 	struct image	*im = plmt->image;
-	u_int		 x, run;
+	u_int		 x, i, run;
 
 	for (x = 0; x < sx; x += run) {
 		if (!image_cell_has_visible_pixels(im, x, src_y)) {
@@ -559,6 +621,8 @@ image_add_row(struct image_line *line, struct image_placement *plmt,
 			if (!image_cell_has_visible_pixels(im, x + run, src_y))
 				break;
 		}
+		for (i = 0; i < run; i++)
+			image_line_cover(line, plmt, cx + x + i, x + i, src_y);
 		image_span_add(line, plmt, cx + x, run, x, src_y);
 	}
 }
diff --git a/image-sixel.c b/image-sixel.c
index c7fc56b3d..c4c8fb23d 100644
--- a/image-sixel.c
+++ b/image-sixel.c
@@ -61,18 +61,25 @@ struct sixel_image {
 	u_int			 dy;
 	u_int			 dc;
 
-	/* Lines of palette indexes. */
+	/* Lines of palette indexes and the bytes allocated for them. */
 	struct sixel_line	*lines;
+	size_t			 allocated;
 };
 
 /* Grow a SIXEL image to contain a line. */
 static int
 sixel_parse_expand_lines(struct sixel_image *si, u_int y)
 {
+	u_int	height = si->y;
+
+	if (y > height)
+		height = y;
+	if (height > SIXEL_HEIGHT_LIMIT)
+		return (1);
+	if (si->x * height > IMAGE_SIZE_LIMIT / 4)
+		return (1);
 	if (y <= si->y)
 		return (0);
-	if (y > SIXEL_HEIGHT_LIMIT)
-		return (1);
 	si->lines = xrecallocarray(si->lines, si->y, y, sizeof *si->lines);
 	si->y = y;
 	return (0);
@@ -82,14 +89,24 @@ sixel_parse_expand_lines(struct sixel_image *si, u_int y)
 static int
 sixel_parse_expand_line(struct sixel_image *si, struct sixel_line *sl, u_int x)
 {
+	u_int	width = si->x;
+	size_t	added;
+
+	if (x > width)
+		width = x;
+	if (width > SIXEL_WIDTH_LIMIT)
+		return (1);
+	if (width * si->y > IMAGE_SIZE_LIMIT / 4)
+		return (1);
 	if (x <= sl->x)
 		return (0);
-	if (x > SIXEL_WIDTH_LIMIT)
+	added = (width - sl->x) * sizeof *sl->data;
+	if (added > IMAGE_SIZE_LIMIT / 2 - si->allocated)
 		return (1);
-	if (x > si->x)
-		si->x = x;
+	si->x = width;
 	sl->data = xrecallocarray(sl->data, sl->x, si->x, sizeof *sl->data);
 	sl->x = si->x;
+	si->allocated += added;
 	return (0);
 }
 
@@ -204,7 +221,10 @@ sixel_parse_attributes(struct sixel_image *si, const char *cp, const char *end)
 	}
 
 	si->x = x;
-	sixel_parse_expand_lines(si, y);
+	if (sixel_parse_expand_lines(si, y) != 0) {
+		log_debug("%s: size limit reached", __func__);
+		return (NULL);
+	}
 
 	return (last);
 }
@@ -320,7 +340,7 @@ sixel_parse_repeat(struct sixel_image *si, const char *cp, const char *end)
 	ch = (*last++) - 0x3f;
 	for (i = 0; i < n; i++) {
 		if (sixel_parse_write(si, ch) != 0) {
-			log_debug("%s: width limit reached", __func__);
+			log_debug("%s: size limit reached", __func__);
 			return (NULL);
 		}
 		si->dx++;
@@ -379,7 +399,7 @@ sixel_parse(const char *buf, size_t len, u_int p1, u_int p2, u_int xpixel,
 			if (ch < 0x3f || ch > 0x7e)
 				goto bad;
 			if (sixel_parse_write(si, ch - 0x3f) != 0) {
-				log_debug("%s: width limit reached", __func__);
+				log_debug("%s: size limit reached", __func__);
 				goto bad;
 			}
 			si->dx++;
diff --git a/screen-write.c b/screen-write.c
index 08e76cedb..7df389867 100644
--- a/screen-write.c
+++ b/screen-write.c
@@ -730,6 +730,10 @@ screen_write_fast_copy(struct screen_write_ctx *ctx, struct screen *src,
 			grid_get_cell(gd, xx, yy, &gc);
 			if (xx + gc.data.width > px + nx)
 				break;
+#ifdef ENABLE_IMAGES
+			if (ctx->flags & SCREEN_WRITE_INPUT)
+				image_damage_screen(ctx, s->cx, s->cy, 1, 1);
+#endif
 			grid_view_set_cell(s->grid, s->cx, s->cy, &gc);
 
 			if (!window_position_is_visible(r, xoff + s->cx))
diff --git a/window-copy.c b/window-copy.c
index 39add5b28..18af79d93 100644
--- a/window-copy.c
+++ b/window-copy.c
@@ -5797,6 +5797,9 @@ window_copy_write_line(struct window_mode_entry *wme,
 	char				*expanded;
 	struct format_tree		*ft;
 	int				 current, mode;
+#ifdef ENABLE_IMAGES
+	int				 flags;
+#endif
 
 	width  = window_copy_line_number_width(wme);
 	if (width >= sx)
@@ -5856,6 +5859,8 @@ window_copy_write_line(struct window_mode_entry *wme,
 	    data->backing->grid, 0, hsize - data->oy + py, content_sx, 1);
 	if (data->image_refresh)
 		image_redraw_area(ctx, width, py, content_sx, 1);
+	flags = ctx->flags;
+	ctx->flags |= SCREEN_WRITE_INPUT;
 #endif
 
 	if (py == 0 && s->rupper < s->rlower && !data->hide_position) {
@@ -5877,6 +5882,9 @@ window_copy_write_line(struct window_mode_entry *wme,
 		screen_write_putc(ctx, &grid_default_cell, '$');
 	}
 
+#ifdef ENABLE_IMAGES
+	ctx->flags = flags;
+#endif
 	format_free(ft);
 }