fix: heading-regex tag corruption, live command toggles, adjacent-file collision, stale selection listeners

- HEADING_REGEX now requires a space/EOL after '#' so tag lines
  (#project ...) are no longer misdetected as headings and corrupted.
- Command enable/disable settings now take effect immediately via
  checkCallback/editorCheckCallback instead of requiring a reload.
- New Adjacent File auto-increments (Untitled.md, Untitled 1.md, ...)
  instead of throwing once Untitled.md already exists.
- Selection-change tracking is delegated from document instead of a
  one-time .cm-content scan, so editors opened after startup are covered.

See CHANGELOG.md for details.

src/Constants.ts

@@ -37,6 +37,10 @@ export const LIST_CHARACTER_REGEX = /^\s*(-|\+|\*|\d+\.|>) (\[.\] )?$/
 // ============================================================
 
 /**
- * Regex for matching heading markers at the start of a line
+ * Regex for matching heading markers at the start of a line.
+ * A valid ATX heading marker is 1-6 `#` characters immediately followed
+ * by whitespace or end of line. This lookahead excludes tag-like
+ * prefixes such as `#project` (no space) from being misdetected as
+ * headings — matches[1] is undefined when there is no valid marker.
  */
-export const HEADING_REGEX = /^(#*)( *)(.*)/
+export const HEADING_REGEX = /^(#{1,6}(?=[ \t]|$))?( *)(.*)/

src/FileHelper.ts

@@ -41,7 +41,9 @@ export class FileHelper {
 	}
 
 	/**
-	 * Create a new file in the same directory as the current file
+	 * Create a new file in the same directory as the current file.
+	 * If "Untitled.md" already exists, finds the next available
+	 * "Untitled N.md" name (mirrors Obsidian's own new-note behavior).
 	 */
 	public async newAdjacentFile(editor: Editor, view: MarkdownView | MarkdownFileInfo): Promise<void> {
 		const activeFile = this.app.workspace.getActiveFile()
@@ -51,7 +53,7 @@ export class FileHelper {
 		}
 
 		const parentPath = activeFile.parent?.path ?? ''
-		const newFilePath = parentPath + '/' + 'Untitled.md'
+		const newFilePath = this.getAvailablePath(parentPath, 'Untitled', 'md')
 
 		try {
 			const newFile = await this.app.vault.create(newFilePath, '')
@@ -62,4 +64,17 @@ export class FileHelper {
 			new Notice(String(e))
 		}
 	}
+
+	/**
+	 * Find the first unused "<basename>.md" / "<basename> N.md" path in a folder
+	 */
+	private getAvailablePath(parentPath: string, basename: string, extension: string): string {
+		let candidate = `${parentPath}/${basename}.${extension}`
+		let n = 1
+		while (this.app.vault.getAbstractFileByPath(candidate) !== null) {
+			candidate = `${parentPath}/${basename} ${n}.${extension}`
+			n++
+		}
+		return candidate
+	}
 }

src/ToggleHeading.ts

@@ -42,7 +42,7 @@ export class ToggleHeading {
 		}
 		const to: EditorPosition = {
 			line: line,
-			ch: matches[1].length + matches[2].length,
+			ch: (matches[1]?.length ?? 0) + matches[2].length,
 		}
 
 		const replacementStr = heading === Heading.NORMAL ? '' : headingStr + ' '
@@ -61,7 +61,7 @@ export class ToggleHeading {
 		const text = editor.getLine(line)
 		const matches = HEADING_REGEX.exec(text)!
 
-		return matches[1].length as Heading
+		return (matches[1]?.length ?? 0) as Heading
 	}
 
 	/**

src/main.ts

@@ -98,13 +98,33 @@ export default class BindThemPlugin extends Plugin {
 		editorCallback?: (editor: Editor, view: MarkdownView | MarkdownFileInfo) => void;
 		callback?: () => void;
 	}): void {
-		if (this.isCommandEnabled(options.id)) {
+		const { id, name, icon, editorCallback, callback } = options;
+
+		// Commands are always registered; enabled state is enforced via
+		// checkCallback so toggling a command in settings takes effect
+		// immediately (hides it from the palette and disables its hotkey)
+		// without requiring a plugin reload.
+		if (editorCallback) {
 			this.addCommand({
-				id: options.id,
-				name: options.name,
-				icon: options.icon,
-				editorCallback: options.editorCallback,
-				callback: options.callback,
+				id,
+				name,
+				icon,
+				editorCheckCallback: (checking, editor, view) => {
+					if (!this.isCommandEnabled(id)) return false;
+					if (!checking) editorCallback(editor, view);
+					return true;
+				},
+			});
+		} else if (callback) {
+			this.addCommand({
+				id,
+				name,
+				icon,
+				checkCallback: (checking) => {
+					if (!this.isCommandEnabled(id)) return false;
+					if (!checking) callback();
+					return true;
+				},
 			});
 		}
 	}
@@ -903,31 +923,36 @@ export default class BindThemPlugin extends Plugin {
 	 * - Programmatic changes → within-word matching
 	 */
 	private registerSelectionChangeListeners(): void {
-		this.app.workspace.onLayoutReady(() => {
-			const MODIFIER_KEYS = [
-				'Control', 'Shift', 'Alt', 'Meta', 'CapsLock', 'Fn',
-			]
+		const MODIFIER_KEYS = [
+			'Control', 'Shift', 'Alt', 'Meta', 'CapsLock', 'Fn',
+		]
 
-			const handleSelectionChange = (evt: Event) => {
-				if (
-					evt instanceof KeyboardEvent &&
-					MODIFIER_KEYS.includes(evt.key)
-				) {
-					return
-				}
-				if (!getIsProgrammaticSelectionChange()) {
-					setIsManualSelection(true)
-				}
-				setIsProgrammaticSelectionChange(false)
+		const handleSelectionChange = (evt: Event) => {
+			if (
+				evt instanceof KeyboardEvent &&
+				MODIFIER_KEYS.includes(evt.key)
+			) {
+				return
 			}
+			const target = evt.target as HTMLElement | null
+			if (!target?.closest('.cm-content')) {
+				return
+			}
+			if (!getIsProgrammaticSelectionChange()) {
+				setIsManualSelection(true)
+			}
+			setIsProgrammaticSelectionChange(false)
+		}
 
-			// Observe CodeMirror 6 editors (new Obsidian editor)
-			document.querySelectorAll('.cm-content').forEach((el) => {
-				this.registerDomEvent(el as HTMLElement, 'keydown', handleSelectionChange)
-				this.registerDomEvent(el as HTMLElement, 'click', handleSelectionChange)
-				this.registerDomEvent(el as HTMLElement, 'dblclick', handleSelectionChange)
-			})
-		})
+		// Delegate from `document` in the capture phase instead of
+		// enumerating `.cm-content` elements once at layout-ready:
+		// editors opened in new panes/splits/tabs after startup get
+		// their own `.cm-content` element and would otherwise never
+		// be instrumented. Capture phase guarantees we observe the
+		// event even if CodeMirror stops propagation during bubbling.
+		this.registerDomEvent(document, 'keydown', handleSelectionChange, true)
+		this.registerDomEvent(document, 'click', handleSelectionChange, true)
+		this.registerDomEvent(document, 'dblclick', handleSelectionChange, true)
 	}
 
 	// ============================================================