ImmediatelyFast 1.16.4 for Minecraft 26.2

Minecraft Java rendering performance

ImmediatelyFast optimizes several client rendering paths, but the useful result depends on the scene and on whether the client is limited by the work it changes. The current creator release for Java 26.2 is 1.16.4, published August 27, 2026, with separate Fabric/Quilt and NeoForge files. Older 1.16.3 metadata on this MineBrush page is superseded.

Current 26.2 files

The project declares no dependencies for these two release records and is licensed LGPL-3.0-or-later. “No declared dependency” does not mean every renderer combination is verified. Match the exact loader file and read the current changelog before moving from an older working version.

Visual correctness comes before an FPS claim

ImmediatelyFast changes paths used to draw user-interface elements, text, entities, particles, and other client content. A higher counter is not a pass when a nametag, item, overlay, particle, or menu disappears. The creator’s current release notes include rendering-specific fixes, which reinforces the need to compare the picture before collecting performance numbers.

Performance also depends on the bottleneck. A GPU-limited shader scene may show little benefit from a CPU-side batching improvement. A busy inventory or entity-heavy scene can behave differently from standing still in an empty world. MineBrush therefore does not promise a percentage gain or an “FPS boost” for every PC.

Install and build a repeatable comparison

1. Duplicate the current Java 26.2 profile and record loader, Java runtime, resolution, VSync, frame cap, render distance, resource packs, and shaders.
2. Capture a baseline in four places: title or settings UI, a text-heavy inventory, a particle or entity scene, and a fixed world viewpoint.
3. Add only the matching ImmediatelyFast 1.16.4 JAR. Leave every graphics setting unchanged.
4. Repeat the same route after the same warm-up time. Compare missing or altered visuals before comparing frame times.
5. Restart once and repeat the most important failing or passing scene so cached state does not decide the verdict.

Use frame-time consistency, not only peak FPS. Record one-percent lows or a simple series of repeatable stutters if your tool provides them, but do not invent precision from a short counter glance.

Troubleshoot corruption, crashes, or no visible gain

If text, nametags, particles, or GUI layers are corrupted, preserve a screenshot and the log, then disable ImmediatelyFast in the copied profile. If the baseline returns, check the current issue tracker for the exact GPU, driver, mod, and option. Change one related compatibility setting only when the creator documents it. Do not use several undocumented flags to hide the symptom.

If there is no measurable gain, confirm that the same workload and settings were used. Test a second relevant scene rather than lowering settings. “No gain here” can be a valid result when the scene is limited elsewhere. If the client fails at startup, verify Fabric/Quilt versus NeoForge and remove an old ImmediatelyFast JAR before assuming 1.16.4 is at fault.

Rollback and update safety

Close Minecraft, retain the latest log and ImmediatelyFast config, remove only its JAR, and relaunch the duplicated profile. Confirm all four visual baselines return. If rolling back from 1.16.4 to 1.16.3, use a copied config or fresh defaults because option sets can change. Keep the old file only as a private known-good rollback under the project license; do not redistribute an unofficial bundle.

Interpret the result without hype

Report the median or stable range from repeated routes, the hardware and driver, and the scene that changed. Separate “no visible gain” from “regression” and “visual failure.” A result on one PC cannot be generalized to every player. If 1.16.4 fixes a specific rendering fault but performs the same as 1.16.3, say exactly that; an honest neutral result is more useful than an unsupported optimization claim.

Sources and boundary

• ImmediatelyFast creator versions
• Creator-owned source and issue tracker

MineBrush rechecked the release on August 28, 2026, less than a day after 1.16.4 was published. We did not run it or benchmark hardware. FPS, frame time, driver compatibility, shader interaction, and correctness in a specific modpack remain unknown. For a complementary occlusion test rather than a duplicate renderer claim, use the Entity Culling guide.