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Preview of 目に優しいフォント置換

目に優しいフォント置換 by 1llum1n4t1

読みづらいフォントを好みのフォントに自動で置き換える Chrome / Firefox 拡張機能。9種類(本文用6種 + 等幅用3種)から選択可能で、MS ゴシック・メイリオ・Yu Gothic などを狙い撃ちで置換します。サイトのデザインを極力崩さずに視認性を大幅に向上。

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About this extension
✨ Features

・🎨 Font Selection: Choose from 6 body fonts and 3 monospace fonts via popup dropdown. Settings auto-save.
・🔘 On/Off Toggle: Easily enable or disable the extension via the popup toggle button.
・⚡ Fast & Lightweight: Optimized for minimal impact on page load speed.
・🔄 Fully Automatic: Works instantly across all websites without configuration.
・📦 Modern Web Support: Supports Shadow DOM elements (works on YouTube and modern web apps).
・🌐 Dynamic Font Detection: Automatically detects fonts requested by sites and incorporates unknown names into the replacement target set.
・🎯 Preserve Intent: Replaces fonts based on their type (Gothic, Serif, or Monospace) to maintain the intended layout.
・🛠️ Broad Coverage: Covers everything from OS standard fonts to popular web fonts like Inter and Roboto.

🔤 Available Fonts

▼ Body fonts (6)
Noto Sans JP, IBM Plex Sans JP, M PLUS 2, Murecho, Zen Kaku Gothic New, LINE Seed JP

▼ Monospace fonts (3)
UDEV Gothic JPDOC, PlemolJP, Moralerspace Neon JPDOC

※ Body fonts support Regular (400) and Medium (500) weight selection (default: Regular). Monospace fonts are fixed at Regular (400). Bold weights are preserved.

🔄 Replacement Logic
・General Fonts (Gothic/Serif/System): Replaced with the selected body font.
・Monospace Fonts & Code: Replaced with the selected monospace font.

📄 License
・Project: MIT License
https://github.com/1llum1n4t1s/ReplaceFontSelect/blob/main/LICENSE
・Bundled fonts: All licensed under SIL Open Font License 1.1
https://scripts.sil.org/OFL
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Permissions and data

Required permissions:

  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
3.0.3
Size
33.53 MB
Last updated
3 days ago (May 14, 2026)
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License
MIT License
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