Fix LT-21845: Find/Replace in Texts doesn't honor match WS initially

.github/check_copilot_docs.py

@@ -133,6 +133,9 @@ def index_repo_files(root: Path):
 
 
 def parse_frontmatter(text: str):
+    # Strip UTF-8 BOM if present
+    if text.startswith("\ufeff"):
+        text = text[1:]
     lines = text.splitlines()
     fm = {}
     if len(lines) >= 3 and lines[0].strip() == "---":
@@ -222,7 +225,7 @@ def validate_file(path: Path, repo_index: dict, verbose=False):
         "current_tree": "",
         "ok": True,
     }
-    text = path.read_text(encoding="utf-8", errors="replace")
+    text = path.read_text(encoding="utf-8-sig", errors="replace")
     fm, body = parse_frontmatter(text)
     if not fm:
         result["frontmatter"]["missing"] = [

.github/detect_copilot_needed.py

@@ -90,7 +90,7 @@ def top_level_src_folder(path: str):
 def parse_frontmatter(path: Path) -> Tuple[Optional[Dict[str, str]], str]:
     if not path.exists():
         return None, ""
-    text = path.read_text(encoding="utf-8", errors="replace")
+    text = path.read_text(encoding="utf-8-sig", errors="replace")
     lines = text.splitlines()
     if len(lines) >= 3 and lines[0].strip() == "---":
         end_idx = -1

.github/plan_copilot_updates.py

@@ -63,7 +63,7 @@ def run_git(cmd: Sequence[str], cwd: Path) -> str:
 def parse_frontmatter(path: Path) -> Tuple[Optional[Dict[str, str]], str]:
     if not path.exists():
         return None, ""
-    text = path.read_text(encoding="utf-8", errors="replace")
+    text = path.read_text(encoding="utf-8-sig", errors="replace")
     lines = text.splitlines()
     if len(lines) < 3 or lines[0].strip() != "---":
         return None, text

.github/scaffold_copilot_markdown.py

@@ -87,6 +87,9 @@ def top_level_src_folder(path: str) -> Optional[str]:
 
 
 def parse_frontmatter(text: str) -> Tuple[Optional[Dict[str, str]], str]:
+    # Strip UTF-8 BOM if present
+    if text.startswith("\ufeff"):
+        text = text[1:]
     lines = text.splitlines()
     if len(lines) >= 3 and lines[0].strip() == "---":
         end_idx = -1
@@ -230,7 +233,7 @@ def ensure_copilot_doc(
 ) -> Tuple[str, Optional[str]]:
     copath = folder / "AGENTS.md"
     if copath.exists():
-        original = copath.read_text(encoding="utf-8", errors="replace")
+        original = copath.read_text(encoding="utf-8-sig", errors="replace")
     else:
         original = ""
     try:

Src/FwCoreDlgs/AGENTS.md

@@ -1,6 +1,6 @@
 ---
-last-reviewed: 2025-10-31
-last-reviewed-tree: 686f899291d7c6b63b4532a7d7d32a41b409d3198444a91f4ba68020df7a99ac
+last-reviewed: 2026-02-20
+last-reviewed-tree: c84b4a50fb902fe4b7c3d7cb91e9d38297e7bd079b969d9400080c016ebf0078
 status: draft
 ---
 anchors:

Src/FwCoreDlgs/FwFindReplaceDlg.cs

@@ -2643,11 +2643,12 @@ public void ApplyWS(FwTextBox fwTextBox, int hvoWs)
 		{
 			CheckDisposed();
 
+			// Select the text before applying WS (LT-21845).
+			fwTextBox.Select();
 			fwTextBox.ApplyWS(hvoWs);
 			if (chkMatchWS.Enabled)
 				chkMatchWS.Checked = true;
 			SetFormatLabels();
-			fwTextBox.Select();
 		}
 
 		/// ------------------------------------------------------------------------------------