Add-ons client

• When uploading or deleting an add-on, the game will now prompt for the required password if it is not present in the `_server.pbl` file.

AI

• Improved AI decisions about whether an attack with poison is better than one with higher direct damage.
• Added options to the Patrol Micro AI on whether to notice invisible units, and on attack range.
• Added a `[filter]` option to the Swarm Micro AI.
• Replaced several uses of Formula AIs with Micro AIs, and removed Formula AIs from demo scenarios.
• Removed experimental MP dev Formula AIs.
• Fixed a crash in the Lurker Formula AI.

Campaigns

• Descent into Darkness
  • Buffed Malin.

• Eastern Invasion
  • Dialogue changes in S07b.

• Legend of Wesmere
  • S16: Replaced the Patrol Formula AI with the Patrol Micro AI.

• Secrets of the Ancients
  • Reimplemented the zombie recruitment UI.

• The Rise of Wesnoth
  • Balance changes (issue #5603).

• The South Guard
  • Fix the new ally's upkeep when choosing the bandit branch.

• Tutorial
  • Reimplemented the character-choice UI.

• Under the Burning Suns
  • In S01, fixed one of the mystics spawning in the lake.

Lua API

• Fix issues with the wesnoth.map module.

Multiplayer

• Dark Forecast
  • Difficulty rebalanced so that two-player-mode is hard rather than impossible (PR #5673).
  • The weather now changes on side 1's turn instead of side 3's turn (issue #5653).

• World Conquest
  • Many bugs have been fixed, however WC is still hidden while more bugs are fixed.
  • Converted GUI2 dialogs to WML.
  • Fixed an error in the destruction mechanic.

Packaging

• Removed the obsolete FindSDL2_ttf cmake module.

Terrain

• Improved transition between human castle ruins and sunken ruins (issue #5611).

Translations

• Updated translations: Chinese (Traditional), Czech, Italian.

Units

• New rock scorpion monster and scorpion zombie variation.
• Rename tusker/gorer references to boars and piglets, to avoid stepping on existing UMC.
• Dune Blademaster gold cost changed from 52 to 57.
• Dune Captain alignment changed from liminal to lawful.
• Dune Cataphract gold cost changed from 61 to 62.
• Dune Firetrooper gold cost changed from 50 to 41.
• Dune Harrier gold cost changed from 46 to 47.
• Dune Luminary gold cost changed from 53 to 38.
• Dune Maruder gold cost changed from 52 to 60.
• Dune Sky Hunter gold cost changed from 47 to 51.
• Dune Spearmaster gold cost changed from 51 to 57.
• Dune Wayfarer gold cost changed from 52 to 55.
• Dune Windbolt gold cost changed from 50 to 49.
• Dune Warmaster gold cost changed from 56 to 57, hp changed from 57 to 59, alignment changed from liminal to lawful.
• Naga Ophidian gold cost changed from 24 to 22, melee damage changed from 7 to 6, ranged damage changed from 10 to 12.
• Naga Ringcaster gold cost changed from 24 to 22.
• Naga Sicarus gold cost changed from 48 to 46, melee damage changed from 10 to 9, ranged damage changed from 12 to 13.
• Naga Zephyr gold cost changed from 50 to 46.
• Wose Sapling gold cost changed from 10 to 11.
• Wose Shaman gold cost changed from 40 to 27, movement points changed from 3 to 4, melee damage changed from 9 to 12, ranged damage changed from 10 to 11, hp changed from 50 to 56.
• Horned Scarab gold cost changed from 12 to 11.
• Fixed the Walking Corpses of some river creatures having poor movement in deep water (issue #5701).
• New descriptions for the Fire Ant, Roc and Sand Scuttler.
• Fixed the Giant Scorpion having an empty variation name.

User interface

• Improved the attack dialog's recommendation about whether an attack with poison is better than one with higher direct damage.
• Added logs folder path to the Game Version dialog on Windows.
• Added built-in Lua engine version to the Game Version dialog and `--report`.
• Made Accelerated Speed toggle announcement not stackable over itself or other announcements.
• Minor adjustments to the sidebar's minimap area in the default game theme to reclaim empty and uneven space back. Note that this WILL break custom WML themes that use the same sidebar graphics as the default theme.
• Minor adjustment to the placement of numerals on the debug clock.
• Players now receive an error message when attempting to save games using illegal file names (issue #5679).
• Fixed text labels containing only a single link becoming empty (issue #5625).
• Separated floating labels' duration from the speed of their eventual fade-out.
• Fixed font family leakage from GUI2 canvases to GUI1 elements such as the in-game chat overlay (issue #5712).

WML Engine

• In development builds, deprecation warnings are now shown in-game by default.
• Conditional WML's `[variable]` tag now expects exactly one comparison, and will warn if given none or multiple tests.
• `[store_reachable_locations]range=vision` now calculates vision, instead of using movement costs and max movement points (issue #4179).

Miscellaneous and Bug Fixes

• Fixed units with max movement set to zero being given one max movement point by `[unstore_unit]` or when loading a saved game (issue #5638).
• Fixed an intermittent crash on the loading screen (issue #5629).
• wmlunits (units.wesnoth.org) no longer incorrectly assumes that units with movement costs equal to their maximum movement can't move into the affected terrains.
• Fixed a bug where log domains' severity could accidentally be reduced.
• Changed the verbosity and error-handling of the `run_wml_tests` script.
• Made `run_wml_tests` automatically skip tests which need strict mode when running without strict mode.
• Made optimizations in the UI drawing code, these shouldn't have visible effects (PR #5697).
• Optimized the command-line `wesnoth_addon_manager` tool.