[TS] Expose optional stack property on Exception (#4381)

Author: MangelMaxime

src/Fable.Cli/CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+* [TS] Expose optional `stack` property on `Exception` (by @MangelMaxime)
 * [Python] Fix `nonlocal`/`global` declarations generated inside `match/case` bodies causing `SyntaxError` (by @dbrattli)
 * [Python] Fix exception variable captured in deferred closures causing `NameError` (PEP 3110 scoping) (by @dbrattli)
 

src/fable-library-ts/CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Fixed
+
+* [TS] Expose optional `stack` property on `Exception` (by @MangelMaxime)
+
 ## 2.0.0-rc.2 - 2026-03-03
 
 ### Fixed

src/fable-library-ts/Util.ts

@@ -79,6 +79,7 @@ export interface ICollection<T> extends IEnumerable<T> {
 // Exception is intentionally not derived from Error, for performance reasons (see #2160)
 export class Exception {
   public message: string;
+  public stack?: string;
 
   constructor(msg?: string) {
     this.message = msg ?? "";