Opening a rendered video inside Studio throws "Unexpected error: content-length is null"

[kuzzmi]

Bug Report 🐛

Regardless of the OS: MacOS, Windows or Linux, whenever I press on a link to open a video inside Studio, I get this message.

I'm using bun, but it's the same for node as well. I don't think I'm doing anything particularly wrong or undocumented. Essentially, I render from the studio, but can't open the rendered output in it.

[JonnyBurger]

Just tested, not getting this in the latest version! Which version are you in?

[kuzzmi]

Just tested, not getting this in the latest version! Which version are you in?

I'm on 4.0.252, but after upgrading to 4.0.255 nothing has changed. That is a plain blank template with updated default Composition, and everything's fine, the video file is fine:

╭─ Starting render 
│ Bundled code         ━━━━━━━━━━━━━━━━━━ 2058ms
│ Composition          Audio-Visualizer
│ Codec                h264
│ Output               out/Audio-Visualizer.mp4
│ Concurrency          5x
│ Rendered frames      ━━━━━━━━━━━━━━━━━━ 14509ms
│ Downloaded assets    ━━━━━━━━━━━━━━━━━━ 1 file
│ Encoded video        ━━━━━━━━━━━━━━━━━━ 1345ms
│ ○                    out/Audio-Visualizer.mp4 889 kB
╰─ Done in 18317ms.

[JonnyBurger]

I think you are running the studio with bun (in package.json remotionb studio was set when initialiting with Bun)

And I think this is a Bun bug, maybe in a recent version, we are indeed setting the content length header.
I am getting a similar error with the renderer in the latest Bun version.

Temporary workaround: Replace remotionb with remotion