Borderless Window

A lightweight client-side mod for NeoForge 1.21.1 that adds borderless fullscreen to Minecraft, replacing the exclusive fullscreen toggle with a proper 3-mode system — plus a configurable FPS overlay and per-type fog toggles.

Features

Three screen modes: Windowed, Borderless, and Minecraft's regular exclusive Fullscreen.
Configurable F11: choose what the key does — toggle Borderless, toggle exclusive Fullscreen, or cycle through all three modes.
FPS overlay: Simple mode shows the current FPS; Extended mode shows a single line with the current FPS plus the Min / Avg / Max over the last 15 seconds. Position configurable (any screen corner). Stats sample the game's own FPS counter, so they always match F3 and respect VSync / FPS caps. Auto-hides while F3 is open.
Fog toggles: disable each fog type independently — Terrain (the distance haze, including the Nether's thick fog), Water, Lava, and Powder Snow. Fog from the Blindness and Darkness effects is never affected, so gameplay mechanics stay intact.
Config screen included: change everything from the Mods menu (select the mod → Config button). No other mod needed.
HDR-friendly: avoids the black-screen flash / color profile switch that exclusive fullscreen (and naive borderless implementations) cause with Windows HDR enabled.
Multi-monitor aware: borderless and fullscreen apply on the monitor the window is currently on, not always the primary one.
Persistent: all settings are remembered between game sessions (config/borderlesswindow.json).
Sodium integration (optional): with Sodium 0.8.x installed, the "Fullscreen" checkbox in its video settings is replaced by a "Screen Mode" selector, and the mod gets its own section with per-feature pages (General, FPS Overlay, Fog). Built entirely on Sodium's official Config API — no fragile mixins into Sodium internals. Also plays nice with Reese's Sodium Options.
Zero required dependencies: works with or without Sodium.
Translatable: all strings live in standard lang files (en_us, es_mx, es_es included — contributions welcome).

Why borderless?

Exclusive fullscreen changes your monitor's actual display mode, which causes slow alt-tabbing, black-screen flashes with HDR, resolution desync bugs, and broken window states when the game restarts. Borderless fullscreen is just a window sized to your monitor with no decorations: it looks identical, but alt-tab is instant and nothing ever desyncs.

Configuration

In game (no Sodium): Mods menu → Borderless Window → Config. Eight options: Screen Mode, F11 Mode, FPS Overlay, FPS Overlay Position, and the four fog toggles. Changes apply instantly.
In game (with Sodium): Video Settings → the "Screen Mode" option (replaces Sodium's fullscreen checkbox) and the "Borderless Window" section with its General, FPS Overlay, and Fog pages.
Config file: config/borderlesswindow.json. If the mod ever gets stuck in a weird state, delete this file and restart — defaults are regenerated safely.

Requirements

Minecraft 1.21.1
NeoForge 21.1.x
(Optional) Sodium 0.8.0+ for the video settings integration

License

MIT LICENSE