Loop throwing an error

[clarjon1]

https://ffmpeg.app/command/loop-a-video
Firefox 119.0 on 64bit win10

Selected video file, hit button to try to loop, get FAILED error underneath dialog. Tested with different random little vids i had laying about. Attached sample and output from console below

Output from firefox dev tools console:

Initializing FFmpeg [index-a4d0a689.js:1:30830](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG] Executing commands: 
Array(7) [ "-i", "input_0.mp4", "-stream_loop", "1", "-c", "copy", "output.mp4" ]
[index-a4d0a689.js:1:32076](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr] ffmpeg version 5.1.3 Copyright (c) 2000-2022 the FFmpeg developers [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   built with emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 3.1.40 (5c27e79dd0a9c4e27ef2326841698cdd4f6b5784) [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   configuration: --target-os=none --arch=x86_32 --enable-cross-compile --disable-asm --disable-stripping --disable-programs --disable-doc --disable-debug --disable-runtime-cpudetect --disable-autodetect --nm=emnm --ar=emar --ranlib=emranlib --cc=emcc --cxx=em++ --objcc=emcc --dep-cc=emcc --extra-cflags='-I/opt/include -O3 -msimd128' --extra-cxxflags='-I/opt/include -O3 -msimd128' --disable-pthreads --disable-w32threads --disable-os2threads --enable-gpl --enable-libx264 --enable-libx265 --enable-libvpx --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libopus --enable-zlib --enable-libwebp --enable-libfreetype --enable-libfribidi --enable-libass [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libavutil      57. 28.100 / 57. 28.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libavcodec     59. 37.100 / 59. 37.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libavformat    59. 27.100 / 59. 27.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libavdevice    59.  7.100 / 59.  7.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libavfilter     8. 44.100 /  8. 44.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libswscale      6.  7.100 /  6.  7.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libswresample   4.  7.100 /  4.  7.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   libpostproc    56.  6.100 / 56.  6.100 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr] Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input_0.mp4': [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   Metadata: [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]     major_brand     : isom [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]     minor_version   : 512 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]     compatible_brands: isomiso2avc1mp41 [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]     creation_time   : 2023-09-02T13:19:20.000000Z [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   Duration: 00:00:25.63, start: 0.000000, bitrate: 399 kb/s [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   Stream #0:0[0x1](eng): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p(tv, unknown/bt470bg/unknown, progressive), 532x720 [SAR 1:1 DAR 133:180], 264 kb/s, 30 fps, 30 tbr, 90k tbn (default) [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]     Metadata: [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]       creation_time   : 2023-09-02T13:19:19.000000Z [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]       handler_name    : VideoHandle [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]       vendor_id       : [0][0][0][0] [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]   Stream #0:1[0x2](eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default) [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]     Metadata: [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]       creation_time   : 2023-09-02T13:19:19.000000Z [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]       handler_name    : SoundHandle [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr]       vendor_id       : [0][0][0][0] [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr] Option stream_loop (set number of times input stream shall be looped) cannot be applied to output url output.mp4 -- you are trying to apply an input option to an output file or vice versa. Move this option before the file it belongs to. [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr] Error parsing options for output file output.mp4. [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr] Error opening output files: Invalid argument [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)
[FFMPEG][stderr] Aborted() [index-a4d0a689.js:1:29629](https://ffmpeg.app/assets/index-a4d0a689.js)

Source video for testing:

doesthisdoanything.mp4