Hi community, this is my first post.
At first I want to thank the makers of Kdenlive for their awesome work! It is a really powerful tool which I love to use for a while now, I even like it more than Vegas.
System: Dualboot: Bodhi Linux 3.0 / Win7; Kdenlive 0.9.6 on Bodhi
Video input source: 1080p30 h264 ~8000kbit/s (.mp4) coming out of my Samsung NX1100
Video render output: 1080p30 h264 ~12000kbit/s (.mp4) for yt upload

My problems:
1. If I am using transparent layers over my video in Kdenlive (such as .png's with transparency or Kdenlive generated Title Clips) the whole video brightens up when the layer becomes visible via Affine/Composite. This happens in the live monitor and in the rendered file.
2. The general colors are somewhat brightened up a bit (h264 known gamma issue?), visible in the live monitor and redered file.
I was able to fix those issues:
After some research I checked the box "force colorspace: ITU-R 601" in the advanced clip settings. => solved issues 1 & 2.

But now it gets really ugly:
I am using the clips for a YT channel and depending on the used browser/OS issues 1 and 2 appear again, although they are NOT visible when I play back the file for the yt upload with VLC under linux. Sometimes it changes when switching between 480p and 720p in yt.
Firefox, Bodhi: Everything correct
Firefox, Win7: Everything correct
Chrome, Win7: Issues 1 and 2, (colors are ruined and video brightens up even more while layers are visible)
Firefox, WinXP: Sometimes it is correct, sometimes issues 1 and 2.
Here is the Video I am talking about: https://youtu.be/d_0Ra0Dg58I
(brightening up is good visible between 0:45 and 0:53, if issues 1 and 2 appear. Try your luck.)

At this point I am starting to believe in ghosts:
Playing back the rendered output file from Kdenlive on different systems:
VLC, Bodhi: Everything correct
VLC, Win7: Issues 1 and 2

I have no idea what is going on here,
I wanted to ask if someone has similar issues or someone can recommend a different output codec for my purpose....
Good video quality in all browsers is my goal.
This is all kind of rage inducting

Comparison right/wrong colors:

C'mon I'm just looking for an output codec which has good fullhd compression and is not h264 (because I am having weird problems with h264)
Self bump.

I doubt it is a container/codec problem. As the trouble is depending on the browser I believe it is a browser/hardware acceleration problem.

If kepping the colors stable on all browsers has a higher priority than filesize, mp4 with a reasonable bitrate may do the trick. If best compression is your #1 goal, h.264 is your friend - but not on all browsers. Unfortunately you can have only one #1.

Ok, thank you.

Big update here:
After upgrading from 0.9.6 to 0.9.10 using the ppa:sunab/kdenlive-release repository all the color trouble is gone!
No more green tint or brightening when using title clips with transperency. Even without forcing a wrong colorspace. The h.264 parameter settings make more sense to me in 0.9.10 too