Fix typos in the comments

startpage.cpp

@@ -804,7 +804,7 @@ void wxStartPage::OnMouseChange(wxMouseEvent& event)
             button.m_rect.Contains(event.GetX(), event.GetY()) )
             {
             m_activeButton = button.m_id;
-            // if its the same active button from before, then don't bother refreshing
+            // if it's the same active button from before, then don't bother refreshing
             if (previouslyActiveButton == m_activeButton)
                 { return; }
             // ...otherwise, just refresh the current and previous (if applicable) highlighted areas

startpage.h

@@ -174,7 +174,7 @@ class wxStartPage final : public wxWindow
             m_buttons[buttonIndex].m_id;
         }
     /// @returns @c true if @c Id is and ID for one of the custom buttons on the left.
-    /// @param Id The ID from an @c wxEVT_STARTPAGE_CLICKED event after a
+    /// @param Id The ID from a @c wxEVT_STARTPAGE_CLICKED event after a
     ///     user clicks a button on the start page.
     wxNODISCARD
     bool IsCustomButtonId(const wxWindowID Id) const noexcept
@@ -183,13 +183,13 @@ class wxStartPage final : public wxWindow
                 static_cast<size_t>(Id) < ID_BUTTON_ID_START + m_buttons.size());
         }
     /// @returns @c true if @c Id is an ID within the MRU list.
-    /// @param Id The ID from an @c wxEVT_STARTPAGE_CLICKED event after a
+    /// @param Id The ID from a @c wxEVT_STARTPAGE_CLICKED event after a
     ///     user clicks a button on the start page.
     wxNODISCARD
     constexpr bool IsFileId(const wxWindowID Id) const noexcept
         { return (Id >= ID_FILE_ID_START && Id < START_PAGE_FILE_LIST_CLEAR); }
     /// @returns @c true if @c Id is the "Clear file list" button.
-    /// @param Id The ID from an @c wxEVT_STARTPAGE_CLICKED event after a
+    /// @param Id The ID from a @c wxEVT_STARTPAGE_CLICKED event after a
     ///     user clicks a button on the start page.
     wxNODISCARD
     constexpr bool IsFileListClearId(const wxWindowID Id) const noexcept