In addition to these settings, there are some tweaks that are activated via JVM flags:

• -Ddtools.launchWorld=WORLD : Automatically loads the world with the folder name WORLD once the main menu is reached. WORLD can be left blank, in this case the most recently played world will be loaded. Hold down shift when the main menu appears to cancel the automatic loading.

• -Ddtools.launchMinimized : Launch Minecraft minimized. Only implemented on Windows at the moment.

• -Ddtools.launchOnDesktop=NUMBER : Launch Minecraft on the virtual desktop with ordinal NUMBER. Only implemented on Linux at the moment. xprop has to be installed for it to work. Only tested on Openbox.

• autoLoadDingOnWorldEntry
  Ding once auto-loaded world is loaded. [default: true]
• autoLoadPauseOnWorldEntry
  Pause some ticks after auto-loaded world is loaded.
  Delaying the pausing can be useful because some initialization like chunk updates won't happen while the game is paused. [default: true]
• autoLoadPauseWaitLength
  How many ticks to wait before pausing an auto-loaded world. [range: 0 ~ 2147483647, default: 20]
• freezeInputKey
  Press F to freeze input.
  (Cheat feature) [default: false]
• chunkpregenerator
  
  • autoInitializeChunkPregenGui
    Auto-initialize Chunk Pregenerator GUI fields. This can be customized in auto_chunk_pregen.ini. [default: false]

• crasher
  Enables debug feature that crashes the game when pressing certain key combinations. [default: false]
• dumpSpawnTables
  Adds a command to dump mob spawn tables [default: true]
• logClassLoading
  Log class loading. Useful for determining the cause of 'mixin was loaded too early' issues. (You should always try adding Mixingasm first though.) [default: false]
• logGlDebug
  Creates an OpenGL debug context and logs debug messages. May reduce performance. [default: false]
• logScreenshotPosition
  Writes the camera coordinates and world seed of each screenshot into .minecraft/dtools/wherewasi/<world_name>.hjson [default: false]
• positionDeltaPrint
  Print change in XYZ coordinates every tick [default: false]
• wireframe
  Render world in wireframe mode. Toggle using /dtools wireframe.
  (Cheat feature) [default: false]
• wireframeStartEnabled
  Enable wireframe at startup [default: false]

• extraRamInfo
  Show extra RAM info in F3 overlay. [default: false]
• forgeBarProfiler
  Creates a report of how long each step of startup loading took in ./dtools/out/fml_bar_profiler.csv. [default: false]
• frameProfilerHooks
  Insert hooks that lets the frame profiler profile various parts of frame rendering. If this is disabled, the frame profiler will only be able to show very limited information. [default: false]
• frameProfilerPrint
  Print render tick times to log periodically. [default: false]
• frameProfilerStartEnabled
  Automatically start frame profiler as soon as the game starts. [default: false]
• methodProfilerMethods
  Comma-separated list of methods to profile. The results will be written to ./dtools/out/profiler-<timestamp>.csv. Currently only the call count is measured. Method names have the syntax of <canonical class name>.<method name>, like some.package.SomeClass.method. [default: ]
• serverRunTimePrinter
  Prints server run time.
  
  You can also set a shell command to be run when the server starts and stops by setting the dtools.serverRunTimePrinter.startCommand and dtools.serverRunTimePrinter.stopCommand JVM flags. Useful for attaching a profiler, for example. [default: false]
• setBlockProfiler
  Logs how many times World#setBlock was called, with breakdowns by caller and block type. The results are written to ./dtools/out/setblockprofiler.txt. Slows down world gen by a lot! [default: false]

• devWorldSetup
  Adds a button to the world creation GUI for convenient setup of test worlds. This can be customized in devsetup.ini. [default: true]
• doWeatherCycle
  Backports the doWeatherCycle game rule. From Et Futurum Requiem.
  Compatibility note: Will be disabled if Et Futurum Requiem is present. [default: true]
• forceReloadSkins
  Force skins to get reloaded when relogging. [default: false]
• gamemodeSwitcher
  Switch gamemode between survival and creative when pressing F3+F4.
  Compatibility note: Will be disabled if Et Futurum Requiem is present. [default: true]
• sprintFlying
  Increase fly speed while sprinting. From Et Futurum Requiem.
  Compatibility note: Will be disabled if Et Futurum Requiem is present. [default: true]
• worldDeleter
  Adds keyboard combinations to quickly delete worlds: Pressing Alt+D in the world selection GUI will delete only the world region data, Shift+D will delete the world completely forever (a long time!) [default: false]
• thaumcraft
  
  • unlockAllAspects
    Show aspects for all items without having to scan them if player is in creative mode. [default: true]