diff --git a/PretextView.cpp b/PretextView.cpp
index 88d0258..83d90f3 100644
--- a/PretextView.cpp
+++ b/PretextView.cpp
@@ -1951,7 +1951,7 @@ MetaTagsEditorRun(struct nk_context *ctx, u08 show)
                 {
                     if (!strlen((const char *)Meta_Data->tags[index]))
                     {
-                        ForLoop2(Number_of_Pixels_1D) Map_State->metaDataFlags[index2] &= ~(1 << index);
+                        ForLoop2(Number_of_Pixels_1D) Map_State->metaDataFlags[index2] &= ~(1ULL << index);
                         u32 nextActive = index;
                         ForLoop2((ArrayCount(Meta_Data->tags) - 1))
                         {
@@ -5973,7 +5973,9 @@ Render() {
                         (char *)"Left Click: pickup, place",
                         (char *)"S: toggle snap mode",
                         (char *)"Middle Click / Spacebar: pickup whole sequence or (hold Shift): scaffold",
-                        (char *)"Middle Click / Spacebar (while editing): invert sequence"
+                        (char *)"Middle Click / Spacebar (while editing): invert sequence",
+                        (char *)"P: copy highlight to clipboard",
+                        (char *)"V: break at selection start"
                     };
 
                     textBoxHeight = (f32)helpTexts.size() * (lh + 1.0f) - 1.0f;
@@ -9874,21 +9876,12 @@ KeyBoard(GLFWwindow* window, s32 key, s32 scancode, s32 action, s32 mods)
                 case GLFW_KEY_V:
                     if (Edit_Mode && action != GLFW_RELEASE)
                     {
+                        // One breakpoint per keypress: V at start of selection (min pixel).
                         u32 start = my_Min(Edit_Pixels.pixels.x, Edit_Pixels.pixels.y);
-                        u32 end = my_Max(Edit_Pixels.pixels.x, Edit_Pixels.pixels.y);
-                        u32 didBreak = 0;
-                        if (BreakMap((int)start, 1))
-                        {
-                            AddBreakEdit(start);
-                            didBreak = 1;
-                        }
-                        if (end != start && BreakMap((int)end, 1))
-                        {
-                            AddBreakEdit(end);
-                            didBreak = 1;
-                        }
-                        if (didBreak)
+                        u32 loc = start;
+                        if (BreakMap((int)loc, 1))
                         {
+                            AddBreakEdit(loc);
                             UpdateContigsFromMapState();
                             UpdateScaffolds();
                             Redisplay = 1;
diff --git a/README.md b/README.md
index 441a721..0b3e201 100644
--- a/README.md
+++ b/README.md
@@ -39,9 +39,8 @@ PretextView is a desktop application for viewing pretext contact maps.<br/>
 ## Edit mode (`E`)
 - `left mouse button`: Click and drag with the left mouse button to select an are to zoom to. 
 - Pickup a region of a contig with the left mouse button, pickup a whole contig with the middle mouse button or spacebar. Place a region with the left mouse button. Invert a selected region with the middle mouse button or spacebar. Undo the last edit with the 'q' key. Exit edit mode with the 'e' key. Use the GUI to see a list of completed edits.
-- `P`: copy the **highlighted** map range to the system clipboard. The text lists each map fragment in the selection with the contig name and a **local** span in megabases along that fragment (not a single genome-wide coordinate). If nothing is actively selected, the current edit cursor range is used. 
+- `P`: copy the **highlighted** map range to the system clipboard. The text lists each map fragment in the selection with the contig name and a **local** span in megabases along that fragment (not a single genome-wide coordinate).
 - `V`: break (split) the contig at the start of the current selection.
-- `Shift` + `V`: break (split) the contig at the end of the current selection.
 
 ## Waypoint mode (`W`)
 - `left mouse button`: place a waypoint.