#157 Client crash (ldebug.c:747 assertion) opening any addon dropdown in the Settings panel on 70009

Status: Closed · Area: UI & Interface · Addons & API

Opening an addon's dropdown menu in the Settings panel crashes the whole game client instead of just showing an error.

Current behavior

On 1.60.1.70009, opening a dropdown that an addon registered through `Settings.CreateDropdown` crashes the client with a fatal error: ERROR #0 (0x85100000) Assertion failure! ((((t))->tt_) == (((5)))) Engine\Source\lua-5.1\src\ldebug.c(747) The Lua stack in the crash report ends in Blizzard code, with no addon frames: `Menu.lua:2212` is `proxy.ownerRegion = ownerRegion`, and the report names the addon as `<Addons.Current>`, so execution is tainted by the addon whose dropdown was opened. Blizzard's own dropdowns on the Game tab open normally. `Menu.lua` is unchanged since 69913, so this looks like a change in the 70009 executable (built 23 Sep).

Expected behavior

The dropdown opens, or at worst a Lua error is raised. An assertion inside the Lua VM should not be reachable from addon code.

How to reproduce

1. Enable any addon that registers a dropdown with Settings.CreateDropdown.
2. Open Options, AddOns, pick that addon's page.
3. Click the dropdown. The client crashes.