diff --git a/src/textual_paint/paint.py b/src/textual_paint/paint.py
index 822612d..a2e3dd6 100755
--- a/src/textual_paint/paint.py
+++ b/src/textual_paint/paint.py
@@ -66,6 +66,8 @@ from textual_paint.windows import (CharacterSelectorDialogWindow, DialogWindow,
 
 MAX_FILE_SIZE = 500000 # 500 KB
 
+DOUBLE_CLICK_TIME = 0.8 # seconds; overridden in tests to avoid flakiness
+
 # Most arguments are handled at the end of the file,
 # but it may be important to do this one early.
 load_language(args.language)
@@ -397,7 +399,7 @@ class CharInput(Input, inherit_bindings=False):
         if event.ctrl or event.button == 3: # right click
             self.app.action_swap_colors()
             return
-        if event.time - self.last_click_time < 0.8:
+        if event.time - self.last_click_time < DOUBLE_CLICK_TIME:
             self.app.action_open_character_selector()
         self.last_click_time = event.time
 
@@ -446,7 +448,7 @@ class ColorsBox(Container):
             secondary = event.ctrl or event.button == 3
             self.post_message(self.ColorSelected(self.color_by_button[button], secondary))
             # Detect double click and open Edit Colors dialog.
-            if event.time - self.last_click_time < 0.8 and button == self.last_click_button:
+            if event.time - self.last_click_time < DOUBLE_CLICK_TIME and button == self.last_click_button:
                 assert isinstance(self.app, PaintApp)
                 self.app.action_edit_colors(self.query(".color_button").nodes.index(button), secondary)
             self.last_click_time = event.time
diff --git a/tests/test_snapshots.py b/tests/test_snapshots.py
index 52fa66a..0a670c6 100644
--- a/tests/test_snapshots.py
+++ b/tests/test_snapshots.py
@@ -1,8 +1,11 @@
 from pathlib import Path
 
 import pytest
+from textual.pilot import Pilot
 from textual.widgets import Input
 
+from textual_paint import paint
+
 # These paths are treated as relative to this file.
 APPS_DIR = Path("../src/textual_paint")
 PAINT = APPS_DIR / "paint.py"
@@ -10,9 +13,12 @@ GALLERY = APPS_DIR / "gallery.py"
 
 LARGER = (81, 38)
 """Large enough to show the entire paint app."""
+LARGEST = (107, 42)
+"""Large enough to show the Edit Colors dialog, which is a bit oversized."""
 
-# Prevent flaky tests due to cursor blinking
+# Prevent flaky tests due to timing issues.
 Input.cursor_blink = False
+paint.DOUBLE_CLICK_TIME = 2.0
 
 @pytest.fixture(params=[
     {"theme": "light", "ascii_only": False},
@@ -61,6 +67,27 @@ def test_paint_view_bitmap(snap_compare):
 def test_paint_invert_and_exit(snap_compare, each_theme):
     assert snap_compare(PAINT, press=["ctrl+i", "ctrl+q"])
 
+def test_swap_selected_colors(snap_compare):
+    async def swap_selected_colors(pilot: Pilot):
+        await pilot.click("CharInput", control=True)
+
+    assert snap_compare(PAINT, run_before=swap_selected_colors)
+
+def test_paint_character_picker_dialog(snap_compare, each_theme):
+    async def open_character_picker(pilot: Pilot):
+        await pilot.click("CharInput")
+        await pilot.click("CharInput")
+
+    assert snap_compare(PAINT, run_before=open_character_picker, terminal_size=LARGER)
+
+def test_paint_edit_colors_dialog(snap_compare, each_theme):
+    async def open_edit_colors(pilot: Pilot):
+        pilot.app.query("ColorsBox Button")[0].id = "a_color_button"
+        await pilot.click("#a_color_button")
+        await pilot.click("#a_color_button")
+
+    assert snap_compare(PAINT, run_before=open_edit_colors, terminal_size=LARGEST)
+
 def test_gallery_app(snap_compare):
     assert snap_compare(GALLERY)