This thread is for keeping track of compatibility problems caused by Fabric mods that don’t currently support Quilt. If you’ve found an incompatible mod (or a mod listed here that is now compatible), please post below with information about it.
When listing an incompatibility, please ensure you’ve reported it to the developer and provide a link to your report! Simply listing mods here does not help get them fixed.
A Note for Editors
This post is intended to mirror the incompatible mods JSON file on the website. Before changing this post, please submit a Pull Request or Issue to the quiltmc.org repository on GitHub. If you can’t do this, please post a note at the bottom of this thread.
Unreported
The following mods are incompatible, and nobody has properly reported this incompatibility (for one reason or another). If possible, please consider generating a usable log, reporting the issue via the project’s official channels, then returning here with a link to your report.
ChatTriggers (GitHub)
ChatTriggers modules are unable to be executed on Quilt due to utilising private Fabric APIs that Quilt doesn’t support.
Pending Support
The following mods are incompatible for one reason or another, but have received issue reports about their breakage. Mods will be here if as long as the authors do not explicitly state they will not be supporting quilt, in which case they will go in the “No support planned” section.
Armored Elytra (Github)
Can cause crashes with QSL’s armor rendering, as it may attempt to render its elytra before quilt knows what entity to provide armor for. Load order dependent as it relies on mixin priority. Author states they plan to fix the incompatibility when they add quilt support some time in the future, see the github issue.
Better Loading Screen (GitHub)
Better Loading Screen is marked incompatible because it gets stuck in an exception loop, repeatedly logging the following message ad infinitum:
java.nio.file.NoSuchFileException: /assets/minecraft/textures/gui/title/mojangstudios.png
For more information, please read the relevant issue on GitHub. However, please note that the developer is not accepting reports regarding non-Fabric loaders, and is too busy to work on this problem for now.
Big Beacons (GitHub)
Contains a mixin incompatible with QSL’s status effect module. See the github issue here. Mixin seems to blame QSL but the issue only occurs with Big Beacons installed alongside.
Combat Enchantments (Github)
Has a mixin incompatibility with quilt. See the relevant github issue. Author seems interested in quilt support but has not been active recently.
Decorative Blocks (GitHub)
Crashes on startup with QSL as its fuel registration does not work with QSL’s REA api, causing a NullPointerException. Merging the open PR would resolve this issue, or users can compile the mod with that patch themselves.
Log Begone (GitHub)
Fails to install its filter into all loggers for unknown reasons, resulting in messages getting through. See either the GitHub issue on Quilt Loader or the support thread in their discord.
More Block Predicates (GitHub)
Uses fabric loader’s internal logger instead of declaring its own, resulting in a crash on startup on quilt, as well as uses of internal fabric apis. See the relevant GitHub issue.
Semitranslucency Fix (GitHub)
Either crashes or makes the entire screen black with a white vignette. See the github issue.
Terraform (GitHub)
Terraform for 1.19.3 crashes on startup with QSL. The Terraform developers consider this to be a Quilt bug, but would accept a PR fixing it on their side.
For more information, please read the relevant Terraform and QSL issues on GitHub.
ViaFabricPlus (GitHub)
Suffers a class cast exception on launch between netty classes only if on linux. See the issue on quilt loader about this. No report has been made to ViaFabricPlus at this time.
Dynmap (Modrinth)
Dynmap crashes the game when using Quilt. Adding the Java argument -Dloader.workaround.jar_copied_mods=dynmap allows the game to launch, but crashes when the world is loaded. Relevant GitHub Issue.
VulkanMod (Github)
Crashes game on startup with quilt loader due to a missing class/class loading issue relating to the vulkan classes. See the github issue.
Deep Mob Learning API: Refabricated
Crashes the game if used in conjunction with mods using QSL APIs, as opposed to just Quilted Fabric API ones. Relevant GitHub Issue
Non-fatal errors
The following mods have errors on Quilt Loader, but are still reasonably able to function normally. Any mods listed here will be posted with an explanation of what’s broken.
Essential (Website)
Essential is marked incompatible because net.fabricmc.loader.metadata.ModMetadataParser appears to be missing from Quilt Loader. However, this is a non-fatal error which only prevents it from being added to Mod Menu - it should still work normally.
Seamless Loading Screen (GitHub)
Seamless Loading Screen is marked incompatible because of an unusual exception thrown when saving and quitting. This is a non-fatal error, but may be causing issues that are invisible to the user.
java.nio.file.FileSystemException: : Is a directory
No support planned
The following mods have confirmed that they have no intention of supporting Quilt. This may be for many reasons — please do not harass developers that do not wish to support quilt.
Codex (GitHub)
Crashes with a shader error on startup. Project has been archived so no issue report can be made, and is unlikely to be fixed
LibJF (GitLab)
LibJF is marked incompatible because it relies on unstable implementation methods in Fabric Loader, specifically getInfo in net.fabricmc.loader.impl.ModContainerImpl. If possible, the mod should be encouraged to find a stable Fabric API call that does what they need.
Support for Quilt in LibJF is not planned. This GitLab issue states that Quilt is unsupported and that things were explained in a discussion on a Matrix channel. Here’s a screenshot of that discussion.
This issue on the Quilt Loader GitHub states that it’s likely to be impossible for Quilt to add support for what LibJF is doing.
For more information, please read the relevant issue on GitHub.
OptiFabric (GitHub)
OptiFabric makes use of Fabric Loader utility classes which are not supported by Quilt Loader - specifically, classes within net.fabricmc.loader.util.version. As these are loader-specific, it’s unlikely that Quilt will support those classes over its own.
For more information, please see this issue on the OptiFabric GitHub. However, please note that this project is essentially dead, and there is very little motivation to maintain it going forward, on Quilt or otherwise - which is why it’s in this category.
Rpg Difficulty (GitHub)
Uses the Fabric API mixin-internal class DefaultAttributeRegistryAccessor, resulting in a mixin error on launch, breaking the game. Developer has stated they have no plans to support or develop for non-fabric loads. See the github issue.
