Fix missing Open Mail button and bump to 1.4.9

- Recreate the Open Mail button if it is missing
- Restore its parent, position, text and click handler
- Ensure the button stays visible above the inbox UI
- Reapply the fix when the mailbox opens or updates
- Bump version to 1.4.9

TurtleMailFix.lua

@@ -8,7 +8,7 @@ local m = TurtleMail
 local getn = table.getn
 local function pack( ... ) return arg end
 
-m.compat_version = "1.4.8"
+m.compat_version = "1.4.9"
 
 local DEFAULT_SENT_FILTERS = {
   Money = 1,
@@ -179,6 +179,69 @@ local function restore_real_mail_widgets_for_upstream()
   if edit_box then m.api.SendMailSubjectEditBox = edit_box end
 end
 
+-- The upstream Open Mail button is created only once in inbox_load(). If that
+-- creation is skipped/interrupted, or another UI addon hides/re-parents the
+-- button afterwards, TurtleMail never recreates it. Keep the button recoverable
+-- whenever the mailbox/inbox is shown or refreshed.
+local function ensure_open_mail_button()
+  local inbox = m.api.InboxFrame
+  if not inbox or not m.api.CreateFrame then return nil end
+
+  local button = m.api.TurtleMailOpenMailButton
+  if not button or type( button.SetPoint ) ~= "function" then
+    button = m.api.CreateFrame( "Button", "TurtleMailOpenMailButton", inbox, "UIPanelButtonTemplate" )
+    m.api.TurtleMailOpenMailButton = button
+  end
+
+  if button.SetParent then button:SetParent( inbox ) end
+  if button.ClearAllPoints then button:ClearAllPoints() end
+  button:SetPoint( "BOTTOM", inbox, "BOTTOM", -10, 90 )
+
+  if button.SetText then button:SetText( m.api.OPENMAIL or "Open Mail" ) end
+
+  local width = 120
+  local font_string = button.GetFontString and button:GetFontString()
+  if font_string and font_string.GetStringWidth then
+    width = math.max( 120, 30 + (font_string:GetStringWidth() or 0) )
+  end
+
+  if button.SetWidth then button:SetWidth( width ) end
+  if button.SetHeight then button:SetHeight( 25 ) end
+  if button.SetScript then button:SetScript( "OnClick", m.inbox_open_all ) end
+
+  if inbox.GetFrameLevel and button.SetFrameLevel then
+    button:SetFrameLevel( (inbox:GetFrameLevel() or 0) + 5 )
+  end
+
+  if button.Enable then button:Enable() end
+  if button.Show then button:Show() end
+  return button
+end
+
+-- Replace the fragile one-shot inbox loader with an idempotent version. This
+-- preserves upstream behavior while making Open Mail recoverable instead of
+-- relying on the initial CreateFrame call succeeding forever.
+function m.inbox_load()
+  if m.api.InboxFrame and m.api.InboxFrame.EnableMouse then
+    m.api.InboxFrame:EnableMouse( false )
+  end
+
+  ensure_open_mail_button()
+
+  for i = 1, 7 do
+    local auction_texture = m.api[ "TurtleMailAuctionIcon" .. i .. "Texture" ]
+    local returned_texture = m.api[ "TurtleMailReturnedArrow" .. i .. "Texture" ]
+    local color = m.api.NORMAL_FONT_COLOR
+
+    if color and auction_texture and auction_texture.SetVertexColor then
+      auction_texture:SetVertexColor( color.r, color.g, color.b )
+    end
+    if color and returned_texture and returned_texture.SetVertexColor then
+      returned_texture:SetVertexColor( color.r, color.g, color.b )
+    end
+  end
+end
+
 -- SavedVariables are not guaranteed to have a valid schema. Repair them before
 -- the original handlers touch nested fields.
 do
@@ -364,6 +427,7 @@ function m.MAIL_SHOW()
   -- recovers if another UI addon changed those globals after addon loading.
   ensure_send_mail_button()
   ensure_subject_edit_box()
+  ensure_open_mail_button()
 
   if not m.api.MailFrame then return end
 
@@ -466,6 +530,8 @@ end
 
 -- Hide stale AH/returned icons on rows that no longer contain mail.
 function m.MAIL_INBOX_UPDATE()
+  ensure_open_mail_button()
+
   if m.inbox_opening then
     m.inbox_update = true
   end