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Automatically translated from Japanese by AI
Seion (Seion) is a writing app for composing poetry, prose, short essays, and social media posts on a screen that values whitespace and silence. We aimed to create a creative environment where "the act of writing itself becomes quietly organized."
Main features:
・Font switching between Mincho / Gothic / Serif / Sans, with adjustable font size, line spacing, character spacing, and text width
・Partial text formatting including bold, italic, underline, text color, and fluorescent markers
・Light / Dark theme, and focus mode that hides left and right panels
・Background image settings (with blur and grayscale overlay adjustments)
・Export written text directly as social media images (1:1 / 9:16 / 16:9) in PNG format. Long texts are automatically split into multiple pages and downloaded with sequential numbering
・Signature image insertion (displayed on the final page only)
・Post aspect ratio display — you can write while maintaining the same text layout as the output image
・PWA support — add to your home screen and use it like an app
All data is saved locally on your device (in the browser's localStorage). No server transmission, account registration, or login required.
Reactions & commentsFeedback1(1)
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保存と復元を、架空のノート1件で試しました。 ①タイトルと本文を保存→再読み込みで両方保持。 ②末尾に一行追記し、保存ボタンを押さずすぐ再読み込みしても、その行が残りました。 ③そのノートをゴミ箱へ移動→復元→再読み込みすると、タイトル・本文・最後の追記がすべて戻りました。初期ノートは変更していません。 AIブラウザ操作での確認で、画像出力やスマホは未検証です。こうした「画面は正常でも最後の編集だけ消える」ケースを、ローカルアプリで繰り返し検査しPlaywrightテストに残すApp Crash Labも作っています。Seion用CLI接続は未検証ですが、仕組みと登録不要デモはこちらです。保存境界の検査に使えるか、ご関心があれば試していただけると嬉しいです。 https://github.com/aichance/business-ai-recipes/tree/main/tools/app-crash-lab
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