Pale Moon forum

In my institute we have to follow some courses about "safety on the workplace". These courses are delivered online by https://sintesiacademy.smartelearning.eu.

Their requirement in the e-mail announcement say: it is necessary to use up-to-date browsers, which are HTML5 compatible if used from mobile devices, or with an appropriate Flash plugin for older versions.. Once entered on the site the "platform characteristics" specify the requirement as Adobe Flash 11 or higher.

I have PM 28.1.0 on opensuse 42 (on an HP desktop, of course). My version of adobe flash is 30.0.0.13.

I went to the site (which is protected by a personal password for each "course student"). The first time I got a notice about a blocked popup (I enabled the site and nothing happened). Once entered I read the general material and started the first course module. In general I can see the static slides and hear the audio, but some of the slides show something which looks like a ... black blackboard, which remains black while a music is playing. I expect some video should appear in it. I get NO error messages. So I interrupted the course.

I would loath using a browser other than PM.
Do you have any suggestions about debugging what is going on, checks in the preference or about:config and so on ?

Edit: I activated the Tools-> Web Developer -> Error Console and saw some warning and error messages there, but I cannot show them here because I cannot copy them or freeze the error console since it continues showing what happens in other browser windows as I move there !

OK, I managed to make screenshots of the Error Console.

When I re-enter the course module (before it starts, when asking me whether I want to resume) I get an error "downloadable font: kern: num_tables is zero, table discarded (font family: ArticulatedBold .... and so on and so forth. I guess this is harmless since I can read the screen, I suppose some replacement font is used.

Then when I go to the window with the "black blackboard" and play starts (at least there is a slide progress bar increasing in the main slide) I see a number of warnings like "HTTP Content-Type of video/mp4 is not supported. Load of media resource .... xxxx.mp4 failed" followed by "Cannot play media. No decoders for requested formats: video/mp4, video/mp4, video/mp4, video/mp4" (verbatim, 4 times) and by "Attempt to set a forbidden header was denied: Host" (twice)

Have you tried playing the video without using Flash?
Assuming the video is just an MP4 video, Pale Moon should be able to play it just fine.

Lucio Chiappetti wrote:I have PM 28.1.0 on opensuse 42

Why not the latest version (28.2.2)?

Are the FFmpeg packages installed on your system?

After some intricated use of the debugger (which also says "video format or mime type not supported", I have been able to download the affected video file, for which the "file" command says

video_22dcaf42-f2c2-4da9-b096-bddc5c8b14bb_24_64_540x304.mp4: ISO Media, MP4 Base Media v1 [IS0 14496-12:2003]

and if I tray to play it offline with the suse-provided utility "dragon" it says

Codec nice name: H.264 (High Profile) decoder
structure: gstreamer1(decoder-video/x-h264)()(64bit)
Did not install codec: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown:

YAST (the suse package manager) says a number of ffmpeg libavcodec are installed, but I am afraid they do not support H.264, according to this page https://en.opensuse.org/SDB:Firefox_MP4 ... eo_Support (and in fact the bundled firefox does not play it as well as palemoon)

See if you have the "ffplay" tool (from the command line) and play the downloaded file with it.
If it doesn't play, ffmpeg doesn't support MP4.
ffplay is part of the ffmpeg suite.

If you're on OpenSUSE you'll need to install the libavcodec packages from a non-free repo.

Thanks for confirming my suspicions. Unfortunately it is not just my problem but at least of half of our staff ... so a solution just on my machine won't solve it... but it is clear it is not a palemoon problem, so I declare the thread closed,

The quick way to see if ffmpeg/libavcodec supports a codec is where you want to see an output line like

Just to conclude, installing libavcodec57 and dependencies from "packman" repository as intstructed in quoted https://en.opensuse.org/SDB:Firefox_MP4 ... eo_Support makes also Pale Moon (now 28.2.2) work with H264 videos.
Better than using chrome (where H264 is built in)