Added, Draw Lines mode: added "Remove First Vertex" action (Ctrl-Backspace). It removes the first drawn vertex from the drawing session. Renamed "Remove Previous Vertex" action to "Remove Last Vertex".
Changed, Classic modes: added a limit on how far the view can be scrolled from the editable map area.
Fixed, Drag geometry modes: in some cases incorrect vertices were removed when using "Replace with dragged geometry" drag mode.
Fixed, Game configurations: sector special 195 ("Hidden Sector") was missing from Hexen/UDMF specials list.

Added, Script Editor: added script configurations / auto-detection support for GAMEINFO, FONTDEFS and KEYCONF text lumps.
Fixed, "Open Map Options" and "Change Map" windows: fixed incorrect size of the items in the maps list when using high-DPI scaling.
Updated ZDoom_DECORATE.cfg and ZDoom_MAPINFO.cfg.

Fixed, Script Editor: Delete key was not working in the text editor (because it was hijacked by context menu action, which requires a selection to be active).

Added, MAPINFO parser: added support for "Skybox" map block property.

Added, Script Editor: added "Find usages" option (available in the "Search" menu, via text editor context menu, via Ctrl-Shift-F shortcut and in the "Find and Replace" window).
Added, Script Editor: double-clicking text resource tab header now shows the corresponding resource in the Resources tree.
Updated, Game configurations, UDMF: added several missing Thing renderstyles.

Updated, Script Editor: redesigned "Find and Replace" window. It can now search/replace in all opened tabs and all detected text resources.
Fixed, Script Editor: resources list control was incorrectly positioned when using DPI scaling.

Fixed, Script Editor: resources navigator was always loading the first WAD lump with matching name when trying to open any of several WAD lumps with matching names.
Reverted, Visual mode: looks like all additional cases of displaying sky hack added in r2755 were actually undefined engine behaviors, not the "proper" shy hack... Reverted implementation to the wiki definition of the sky hack.

Fixed, Tag Explorer: in some cases Tag Explorer update logic was switching focus from the Script Editor to the main window.

Updated, Script editor: script editor was unable to show error location after double-clicking on it in the Warnings and Errors window when said location was inside of a WAD located in a PK3 file.
Updated, text lumps tracking: already parsed DECORATE/GLDEFS lumps are now added to the text lumps list even when DECORATE/GLDEFS parsing fails, allowing you to fix errors without the need to use external tools.
Fixed: in some cases the editor could stuck in an infinite loop when searching for wad lumps.

Fixed, Script Editor: Cut/Copy/Paste/Undo/Redo keyboard shortcuts were handled incorrectly when quick search textbox was focused.
Fixed, Script Editor: Find next/Find previous quick search button actions were handled incorrectly.
Updated documentation.

Added, Errors and Warnings window: most of warnings/errors related to (G)ZDoom text lump parsing can now be double-clicked to show warning/error source in the Script Editor.
Fixed: some map format conversion errors were never displayed, because errors list was cleared after performing map conversion.
Fixed: 3d floor indicators in 2D modes were not updated after leaving Visual mode.
Fixed: some UDMF-only interface buttons were never removed after converting map format from UDMF.

Added, Script Editor: MENUDEF and SBARINFO files/lumps are now shown in the Resources list.
Fixed, ACS handling: fixed a crash when trying to parse an #include file, when specified path was absolute.

Added, Script Editor: added "Script Navigator" tab. It shows and allows to open text resources loaded by the editor.
WARNING: because of the large amount of added/modified code, bugs are possible, so backup your resources, save often and report bugs.

Added, Game configurations, ZDoom: Ambient sound things (14001 - 14064) were missing arguments definitions.
Fixed, Make Sectors mode: in some cases sector shape detection logic returned incorrect shape, or no shape at all.

Fixed, Things mode: fixed a crash when deleting Light/Ambient Sound things when "Show Dynamic Light Radii" / "Show Ambient Sound Radii" settings were enabled.
Fixed: WAD lump index was not appended to lump name when reporting errors during ZDoom text lumps parsing.

Fixed, Draw Rectangle mode: fixed a crash caused by incorrectly changing text labels array when accepting the drawing.
Fixed, "Check unknown ACS scripts" error check: named scripts check was performed incorrectly causing it to fail on script names containing uppercase letters.

Fixed, Visual mode, UDMF: "lightfloor" sector property was not applied when calculating thing brightness.
Fixed, Directional Shading mode: "lightabsolute" / "lightfloorabsolute" properties were checked incorrectly.

Added "Apply Directional Shading" mode. It can be used to apply directional colored flat shading to sloped terrain sectors (line and vertex slopes are supported) and sidedefs.
Updated ZDoom ACC.
Updated ZDoom_ACS.cfg.

Changed, Game configurations: "default" property is no longer mandatory for universal field definitions.
Fixed, Game Configurations window: map resources were not marked for reloading after pasting resources to currently used game configuration.
Fixed, Game configurations: "Platform Generic Change" action's arg2 value must be in octics.

Fixed: copied sidedef settings were not applied when using "Paste properties" and "Paste properties special" actions in Doom/Hexen map formats.

Fixed map lumps duplication when saving the map several times after converting the map from/to UDMF map format by changing it in the Map Options window.
Fixed, cosmetic: in some cases incorrect resource loading time was displayed after saving the map.

Changed, Sector drawing: sector height is set to 0 when the nearest sector's height is < 0 (previously default sector height was used when the nearest sector's height was <= 0).

Removed, GLDEFS parser: removed GLOOME glow definitions support code.

A minor code refactoring.

Updated, Curve Linedefs mode: distance/angle are now changed using bigger increments when being modified by mouse-dragging. You can hold Shift to enable increments by 1 unit.
Updated, Curve Linedefs mode: changing angle by mouse-dragging when "Fixed circular curve" option is enabled is now performed in a more predictable way.
Updated, Curve Linedefs mode: generated geometry is now merged with existing geometry.
Added, Curve Linedefs mode: a hint label is now displayed when modifying settings using mouse-dragging.
Added, Curve Linedefs mode: number of curve vertices can now be changed using LMB+RMB-drag.

Optimized map geometry merging performance when pasting map geometry.
Added, Curve Linedefs mode: added "Flip Curve" button.
Updater: partially rewrote fix from the previous commit.

Changed, Curve Linedefs mode: re-designed the mode UI. Alternative control options are now available (check Help tab while the mode is active).
Changed, Curve Linedefs mode: changed curve generation logic. Setting Distance to 0 will now divide selected linedefs into equal parts.
Changed, Curve Linedefs mode: curve vertices are now drawn.
Updated ZDoom_DECORATE.cfg.

Added, Game configurations: added "ignoreddirectories" parameter. It lists directory names to be ignored when loading PK3/PK7/Directory resources.
Added, Game configurations: added "ignoredextensions" parameter. It lists file extensions to be ignored when loading PK3/PK7/Directory resources.
Updated: sector triangulation logic now works ~20% faster.
Changed: a case when a pk3/pk7 archive contains several entries with identical filename is now treated as a warning, not as an error.
Fixed, Visual mode: absolute floor/ceiling brightness should not be affected by brightness transfer effects (like 3d floors).
Fixed, Draw Lines mode: in some cases unclosed sectors were created when several points were successively drawn at the same location.
Updated documentation. 

Updater: moved SharpCompress code into a separate embedded library. Seems to stop some anti-viruses detecting it as a trojan/virus.
Updated ZDoom_DECORATE.cfg (A_SetInventory).