Crash when using "close all but this" on a tab

Problem Description

Construct 2 crashes when I have more than 30 layout tabs open and try to use "close all but this" on any tab. The following message pops up:

---------------------------

Construct 2 Check failure

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Check failure! This is probably a bug:

Last clicked tab is NULL

Condition: last_clicked_tabwnd != NULL

File: MainFrm.cpp

Line: 1977

Function: void __cdecl CMainFrame::OnCloseAllButTab(void)

Build: release 248 (64-bit) checked

Component: Construct 2 IDE

(Last Win32 error: 0)

Attach a Capx

https://www.dropbox.com/s/eec6cfrl540ocrt/close%20all%20bug.capx?dl=0

Description of Capx

An empty project with 30 layout tabs open.

Steps to Reproduce Bug

• Click ok on the "you have over 30 layout tabs open...." popup window.
• Right click on any layout tab and choose "close all but this".

Observed Result

Construct 2 crashes.

Expected Result

All other tabs should be closed without Construct 2 crashing.

Affected Browsers

• Chrome: (YES)
• FireFox: (YES)
• Internet Explorer: (YES)

Operating System and Service Pack

Windows 10 1703

Construct 2 Version ID

248

I can't reproduce any problem here following those steps. I tried doing "close all but this" on Layout 7 and again with Layout 12 and it worked fine. Based on the error message though I've added in an extra check for the next build, which might fix it.