diff --git a/package.json b/package.json
index ade9ab5..61c069d 100644
--- a/package.json
+++ b/package.json
@@ -85,12 +85,14 @@
 					"enum": [
 						"debug",
 						"info",
+						"warn",
 						"error",
 						"off"
 					],
 					"markdownEnumDescriptions": [
-						"Log debug, info, and errors",
-						"Log info and errors",
+						"Log debug, info, warnings, and errors",
+						"Log info, warnings, and errors",
+						"Log warnings and errors",
 						"Log errors only",
 						"Disable logging"
 					],
diff --git a/src/configuration.ts b/src/configuration.ts
index 720870e..1ce5802 100644
--- a/src/configuration.ts
+++ b/src/configuration.ts
@@ -1002,6 +1002,7 @@ export class Configuration {
 				),
 			},
 		};
+
 		logger.debug("Environment:", env);
 
 		// Log the extension's user configuration settings.
diff --git a/src/extensionData.ts b/src/extensionData.ts
index 3d9305e..dbdeac4 100644
--- a/src/extensionData.ts
+++ b/src/extensionData.ts
@@ -350,10 +350,12 @@ export class ExtensionData {
 
 	/**
 	 * Get all extension discovery paths.
+	 * Used for logging the paths to the output channel.
 	 *
 	 * @returns {ReadonlyMap<keyof ExtensionPaths, string>} A read-only Map containing all extension discovery paths.
 	 */
 	public getAllExtensionDiscoveryPaths(): ReadonlyMap<keyof ExtensionPaths, string> {
-		return this.extensionDiscoveryPaths;
+		// Return a new Map to prevent external mutation of the internal state.
+		return new Map(this.extensionDiscoveryPaths);
 	}
 }
diff --git a/src/interfaces/utils.ts b/src/interfaces/utils.ts
index 6f174fb..4291e79 100644
--- a/src/interfaces/utils.ts
+++ b/src/interfaces/utils.ts
@@ -44,6 +44,7 @@ export type LanguageId = string;
 export const logLevels = {
 	debug: "debug",
 	info: "info",
+	warn: "warn",
 	error: "error",
 	off: "off",
 } as const;
diff --git a/src/logger.ts b/src/logger.ts
index 2a86931..accf73d 100644
--- a/src/logger.ts
+++ b/src/logger.ts
@@ -1,3 +1,4 @@
+import * as os from "node:os";
 import {OutputChannel, window} from "vscode";
 import {LogLevel, logLevels} from "./interfaces/utils";
 
@@ -26,6 +27,14 @@ class Logger {
 	 */
 	private logLevel: LogLevel = "debug";
 
+	/**
+	 * Whether the user has already been warned that username redaction is unavailable,
+	 * so the warning is only emitted once per session.
+	 *
+	 * @type {boolean}
+	 */
+	private hasWarnedAboutRedactionFailure: boolean = false;
+
 	/***********
 	 * Methods *
 	 ***********/
@@ -121,6 +130,17 @@ class Logger {
 		}
 	}
 
+	/**
+	 * Sends a warning log to the output channel.
+	 *
+	 * @param {string} message The message to be logged.
+	 */
+	public warn(message: string): void {
+		if (this.shouldLog("warn")) {
+			this.logMessage("WARN", message);
+		}
+	}
+
 	/**
 	 * Send an important message to the output channel.
 	 * This is a special log level that is always emitted regardless of the log level,
@@ -150,8 +170,9 @@ class Logger {
 	private shouldLog(requiredLevel: LogLevel): boolean {
 		// Numeric weights used for level comparison.
 		const levelWeight: Record<LogLevel, number> = {
-			debug: 3, // Emits debug, info, and error logs - the most verbose level.
-			info: 2, // Emits info and error logs.
+			debug: 4, // Emits debug, info, warn, and error logs - the most verbose level.
+			info: 3, // Emits info, warn, and error logs.
+			warn: 2, // Emits warn and error logs.
 			error: 1, // Emits error logs only.
 			off: 0, // Disables all logs, except for the special "important" logs that are always emitted.
 		};
@@ -208,7 +229,7 @@ class Logger {
 			data = lines.join(",\n");
 		}
 
-		return data;
+		return this.redactUsername(data);
 	}
 
 	/**
@@ -232,6 +253,51 @@ class Logger {
 
 		return value;
 	}
+
+	/**
+	 * Redact the OS username from a string, replacing it with `<redacted>`, to avoid leaking
+	 * it into debug logs that could be shared.
+	 *
+	 * @param {string} text The text to redact.
+	 * @returns {string} The text with OS username replaced with `<redacted>`.
+	 */
+	private redactUsername(text: string): string {
+		let username: string;
+
+		// Get the current OS username using Node's userInfo() method which is
+		// cross-platform compatible. It can throw an error in sandboxed/remote environments where
+		// the username can't be determined. So catch any errors and return the original text
+		// if we can't get the username.
+		try {
+			username = os.userInfo().username;
+		} catch {
+			this.warnOnRedactionFailure();
+			return text;
+		}
+
+		// If the username is empty, return the original text.
+		if (!username) {
+			this.warnOnRedactionFailure();
+			return text;
+		}
+
+		// Escape special characters in the username.
+		const escapedUsername = username.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
+		// Replace any occurrence of the username in the text with "<redacted>", case-insensitively, and return it.
+		return text.replace(new RegExp(escapedUsername, "gi"), "<redacted>");
+	}
+
+	/**
+	 * Warn once per session that debug logs may not have the username redacted,
+	 * so users don't unknowingly share it in a bug report.
+	 */
+	private warnOnRedactionFailure(): void {
+		if (this.hasWarnedAboutRedactionFailure) {
+			return;
+		}
+		this.hasWarnedAboutRedactionFailure = true;
+		this.warn("Could not determine OS username; debug logs may not be redacted before sharing.");
+	}
 }
 
 export const logger = new Logger();