Added, Visual mode: "Increase/Decrease Scale", "Reset Texture Offsets" and "Reset Local Texture Offsets" actions now work when used on 3d floor sides.
Fixed: CVARINFO parser was unable to parse negative int/float values.
Fixed: in some cases TextLabel text size was checked before it was calculated. 
Internal, Visual mode: reduced the number of unnecessary geometry updates when changing map geometry.
Updated ZDoom_DECORATE.cfg (atan2 and VectorAngle).

Fixed, Linedefs mode: fixed a crash on undoing linedef draw when trying to update a text label for disposed linedef.

Fixed, Script Editor: fixed infinite loop when trying to search for empty string.
Changed, Linedefs mode: selection labels are now positioned in a less line angle obscuring way.
Changed, Draw Lines mode: text label background alpha didn't match the alpha of the labels used in other classic modes.
Updated ZDoom_ACS.cfg (SetMusicVolume).
Updated ZDoom ACC (SetMusicVolume).

Added: dynamically added side panel tabs now play notify animation when the side panel is collapsed.
Added, Game configurations, ZDoom: added Sector effect 90 (Skybox sector).

Internal: added CVARINFO parser.

Updated ZDoom_DECORATE.cfg.

Added, Game configurations: added "Enum option + enum bits":26 action argument type. It can be used when an argument combines both exclusive and bit flag values.
Updated, Game configurations: some linedef action arguments now use type 26.
Updated documentation ("Game Configuration - Action Argument Settings").
Updated ZDoom ACC (APROP_MaxStepHeight and APROP_MaxDropOffHeight).

Re-fixed: fixed a crash when determining sprite angles when there was more than one sprite for the same frame and angle.

Fixed: fixed a crash when determining sprite angles when there was more than one sprite for the same frame and angle.

Fixed: fixed a crash when determining sprite angles when there were sprites for both rotated (like TESTA2A8) and non-rotated (like TESTA0) versions of the same frame.
Fixed, Tags Selector control, UDMF: in some cases tags adding/removing worked unreliably when mixed tag values were used.
Fixed, Arguments control: in some cases ending colon was not appended to argument names.
Updated ZDoom_ACS.cfg.
Updated ZDoom_DECORATE.cfg.

Fixed, Visual mode: in some cases "Flood-fill textures" actions were not working when "use long texture names" Map Options setting was enabled.

Added, Game configurations: added "Polyobject number":25 argument type. When set, used polyobject numbers will be displayed in the action argument dropdown.
Added, Map Analysis mode: Polyobj_ExplicitLine action was not checked by "Check polyobjects" check. 
Updated ZDoom_linedefs.cfg and Hexen_linedefs.cfg (polyobject number linedef args now have type 25).
Updated documentation ("Game Configuration - Action Argument Settings").

Added, GLDEFS parser: light name can have spaces too, so it also can be quoted...
Removed some excessive quote stripping from most of the ZDoom-related text parsers.
Some parsing error reporting improvements in MODELDEF and GLDEFS parsers.
Added a special warning when a texture/flat is overridden by a cameratexture.

MODELDEF parser: rewrote most of the parser logic. Now it picks actor model(s) based on Frame / FrameName properties.

Fixed, Things mode: in some cases selection labels were not updated after editing a thing.
Fixed, Things mode: selection labels were positioned incorrectly on things with FixedSize setting.
Fixed, Sectors mode: fixed a crash when selecting self-referencing sector when selection labels were enabled.
Fixed, Visual mode: in some cases Auto-align texture actions were not working when "use long texture names" Map Options setting was enabled.
Fixed, MD2/MD3 loader: available animation frames upper bound check was performed incorrectly, which would cause a crash in some very special cases.
Fixed, Game configurations: most Hexen/ZDoom teleport actions use TeleportDests as teleport targets, not MapSpots.

Added, Linedefs mode, Things mode: selection numbers can now be displayed and can be toggled using the "View Selection Numbering" mode toolbar button.
Added, Linedefs mode, Things mode: sector tags can now be displayed and can be toggled using the "View Sector Tags" mode toolbar button.
Fixed, Classic modes, DB2 bug: in some cases text label size was queried before it was calculated, resulting in text labels being rendered when they shouldn't.
Updated ZDoom_DECORATE.cfg (A_LogFloat).

Added, Game configurations: added "targetclasses" argument property. Can be used with argument type 14 (Thing Tag). When set, only things of given classes will be shown in the argument dropdown list in Edit Things window.
Changed, Classic modes: when "Fixed Things Scale" option is enabled, things will now switch to fixed size rendering mode when their visible size is less than 48 pixels.
Changed, Classic modes: changed the fixed size of things with FixedSize setting to 28 pixels.
Updated documentation ("targetclasses" argument property).

Fixed, Classic modes: thing sprite should always be rendered when it's size is affected by "Fixed Things Scale" option or FixedSize setting.
MAPINFO parser: removed a misleading warning.

Rearranged some settings in the Preferences window.

Changed, Texture Browser window: "All" textures group is now saved/reselected like the rest of the texture groups when closing/opening the window.
Changed, Classic modes: bigger Thing arrows are now rendered when thing sprite rendering is skipped.
Changed, Classic modes: when "Fixed Things Scale" option is enabled, thing size stays at 2x scale instead of 1x when extra bounding box is rendered.
Added Preferences -> Appearance -> "Things transparency (Things mode)" slider.
Renamed Preferences -> Appearance -> "Things transparency" to "Things transparency (other modes)".
Externalized thing bounding box and arrow texture, used to render things in Classic modes (Textures/ThingTexture2D.png).
Updated ZDoom_DECORATE.cfg (A_SetUserVarFloat, A_SetUserArrayFloat).

Internal, API: TextLabels can now display multi-line text, their font can be changed, they can have a background.

Added Preferences -> Appearance -> "Things transparency" slider. It controls Things transparency in all classic modes except Things mode.
Added Preferences -> Appearance -> "Hidden Things transparency" slider. It controls transparency of Things hidden by Things filter in Things mode, of all things :)

Fixed, Script Editor: in some cases unwanted characters were inserted when using keyboard shortcuts.
Fixed, Script Editor: auto-completion was not invokable when typing ACS directives.

Fixed occasional TreeView flickering in Edit Things window, Browse Action window and Tag Explorer panel.
Updated Thing category icons in the Edit Things window. They now have "opened" and "closed" states.
Internal: added BufferedTreeView to the core controls.
Updated ZDoom game configurations (sector crush mode).
Updated ZDoom ACC.

Added, Preferences -> Appearance: added "Anisotropic filtering" and "Edge Antialiasing" settings. Also regrouped some settings.
Added, "Check polyobjects" error check: added a check for matching Polyobject and Mirror Polyobject numbers of Polyobj_StartLine action.
Changed, Visual mode: anisotropic filtering is now always applied (previously it was applied only when bilinear filtering was enabled).
Fixed, Visual mode: in some cases light values were incorrectly transferred between 3d floors and regular floors/ceilings.
Fixed, ACS parser: includes for each library must be stored separately (fixes inability to compile a script with an included library, which in turn includes files already included by the script).

Fixed, Map Analysis mode, DB2 bug: "Flip Linedef" fix for "Check line references" check was applied incorrectly.

Fixed, "Check Polyobjects" error check: an error is no longer added when "Mirror Polyobject Number" of "Polyobj_Startline" is 0.
Fixed, "Find and Replace" mode: "Find and Replace" window no longer closes when no results are found and Replace mode is enabled.
Changed, "Find and Replace" mode: renamed some search modes for better grouping.

Fixed, Visual mode: alpha-based texture picking didn't work correctly on HiRes images.
Fixed, Visual mode: fog density was calculated incorrectly for things lit by dynamic lights.
Fixed, Edit Sector window, UDMF: "Fade" and "Light" color pickers initial values were incorrect when displaying mixed values.
Fixed, Edit Thing window, UDMF: "Color" color picker initial value was incorrect when displaying mixed values.

Changed, Draw Lines and Draw Curve modes: "Auto-finish drawing" option now works regardless of "Continuous drawing" option (previously it worked only when the latter was enabled). 
Changed: position and size of the "Errors and Warnings" window is now stored while the editor is running.
Internal: rewritten parts of long texture names support code. It now involves much less special handling.
Updated ZDoom_DECORATE.cfg (A_QuakeEx, A_CheckBlock).
Updated ZDoom_ACS.cfg (QuakeEx).
Updated ZDoom ACC (QuakeEx).

Fixed: HiRes images should be loaded from subdirectories too.
Fixed: in some cases the editor was unable to locate existing "LoRes" images when loading HiRes images.
Disabled some HiRes-related warnings, because the editor doesn't track all sprites or graphics.

Added "Sidedef Lower Texture", "Sidedef Middle Texture" and "Sidedef Upper Texture" Find and Replace modes.

Fixed, Game configurations: some Generic_Floor:200 and Generic_Ceiling:201 parameters were named incorrectly.

Changed, Select Similar Sectors action: when "Effect" option is enabled, all sectors with at least one matching generalized/predefined effect will be selected.
Added, Tag Explorer plugin: a separate category for each generalized/predefined effect is now created when "Sort by action special" sort mode is used.
Added, Edit Effect window: normal and generalized effects can now be set at the same time.
Fixed, Edit Action window: in some cases Generalized actions were incorrectly processed.
Fixed, Edit Effect window: in some cases Generalized effects were incorrectly processed.
Fixed, Select Similar window: Tab control was incorrectly anchored.
Fixed, Nodes Viewer mode, cosmetic: segs angles were calculated incorrectly when showing nodes in classic format.
Fixed: HiRes textures, which didn't override any texture or flat were not loaded. 
Fixed, Tag Explorer plugin: linedef action categories were missing title when "Sort by action special" sort mode was used.
Cosmetic: renamed "Grid Setup" action to "Grid and Backdrop Setup".

Internal: removed some duplicate casts, marked some classes is IDisposable, some streams were disposed more than once.

A warning is now displayed when map uses more than one official IWAD as a resource.

Map saving: map lumps position in the wad is now kept persistent when saving it (previously / in DB2 map lumps were always pushed to the end of the wad when saving it). 
Internal: added NeutralResourcesLanguageAttribute to all assemblies. Theoretically this should result in a bit better performance when accessing embedded resources.
Updated ZDoom_DECORATE.cfg (A_Chase flags).