[zeditor] Switching to Fullscreen crash-to-desktop

Steps to recreate:

1. Etc->Fullscreen
2. Click 'Yes' on the "Fullscreen Warning" msgbox
3. Observe "Microsoft Visual C++ Runtime Library" error:

Code:

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Debug Assertion Failed!

Program: E:\zc\dev\ZeldaClassic\build\Debug\zeditor.exe
File: minkernel\crts\ucrt\src\appcrt\heap\debug_heap.cpp
Line: 908

Expression: is_block_type_valid(header->_block_use)

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Code:

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ZC Editor
Version: 2.55 Nightly (Alpha 119/120)
Tag: 2.55.0 Nightly (Alpha 119/120)
Build Date: 22nd February, 2024 at @ 03:04:45 EST
Dev Signoff: UNSIGNED
QR:##B343AFAF01C281A00DA58A4211A608DFDF080001362A0410FC5306FE2A274100381B02044031300000065824C00000000000D0032301090000000000000000000000000000000000000000000000000034866C3140320200000000000000000000000000##

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Commenting out this line from popup_zqdialog_end() in render.cpp fixes it:

Code:

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delete to_del;

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allowing switching between Fullscreen and Windowed mode freely.