Subtitle Edit 4 is now in bug-fix-only-mode

[niksedk]

Subtitle Edit 4 is now in bug-fix-only mode.
I don’t have time to actively maintain both SE4 and develop the new SE5, so focus will be on the SE5 rewrite.

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SE4 (Current Version)

• Built with WinForms on .NET Framework 4
• Will continue to receive bug fixes and third-party component updates for some time
• Still stable and recommended for production use

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SE5 (Next Generation)

• UI rewritten using Avalonia UI and .NET 10
• Designed to be cross-platform (Windows, macOS, and Linux)
• Aims for a modern, maintainable architecture

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Why the Rewrite?

• Future-proofing as WinForms/.NET 4 become increasingly hard to maintain — especially on Linux
• Modern tech stack for better maintainability, performance, and developer contributions
• True cross-platform support

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Current Status

SE5 is not ready yet, but early preview builds are available here:
https://github.com/niksedk/subtitleedit-avalonia/releases

Features

Feature	SE 4.x	SE 5
Subtitle formats	✅	✅
Video player	✅	⚠️ libmpv
Audio waveform	✅	✅
Audio Spectrogram	✅	✅
Auto-translate	✅	✅
OCR	✅	✅
Batch convert	✅	✅
Plugins	✅	❌

Platform support

Platform	SE 4.x	SE 5
Windows	✅	⚠️ Windows 10+
macOS	❌	✅
Linux	⚠️ Mono	✅

Notes

• Some advanced features are still being completed or refined
• SE 4.x and SE 5 can be installed and used side by side (install portable version on Windows)
• Feedback is especially welcome from macOS and Linux users and users with advanced workflows

New/improved stuff in SE 5

• Video - Re-encode
• Video - Cut video
• Settings with search
• Visual Sync with waveform
• Follow system-theme (dark/light mode)
• Delete many lines in grid/list-view is fast
• Pick folder dialog (did not exist in Winforms 4.x)
• Cleaner UI (High-DPI support on Windows)

[Purfview]

Do you have approximate ETA for SE5 beta?

[niksedk]

Hard to say, hopefully around February.
The TODO list is mainly "Batch convert", OCR, ASSA, and translation stuff - and bug fixes.

[abc16361]

SE-Avalonia looks nice on my 4K desktop, sharp and clean. Menu and Settings are well organized. For improvement, users could give feedback when they use it. To me it looks quite promising and I'm really looking forwards to a beta version with all those features on V4.

[momith]

"UI rewritten using Avalonia UI", but will it also work via Web browser? "Cross-platform" sounds nice, but it would be way better if it also supports client/server. If Im too late with my request, maybe at least the UI can be decoupled? See #10045

[mtsubs]

Two long-awaited improvements have finally arrived:

• High-DPI support on Windows
• Official macOS support!!!

Huuuuuge thanks for building SE5, my sincere respect

-- from Meow P

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and translation stuff

How can I help translate the UI?

A lot of people on our subtitle community ( @MontageSubs ) rely on SubtitleEdit. I can provide a Simplified Chinese translation and would be glad to contribute.

[ArsenTech]

I think the Subtitle Edit v5 will look better