Will paste the string here next time that happens. Until then I'm changing the status into "NEEDSINFO".

<kdenlive-scene audioTracks="2" documentid="1723127761002" duration="153" fps="60" mainClip="17" masterTrack="2" offset="184422" videoTracks="2">
 <clip audioStream="1" binid="4" id="17" in="184422" out="184574" playlist="0" position="184422" speed="1.000000" state="1" track="2">
  <effects parentIn="184422">
   <effect id="crop">
    <property name="center_bias">0</property>
    <property name="center">0</property>
    <property name="right">1940</property>
    <property name="bottom">280</property>
    <property name="use_profile">1</property>
    <property name="left">340</property>
    <property name="top">1000</property>
   </effect>
  </effects>
 </clip>
 <bin>
  <chain id="chain0" out="493028" type="3">
   <property name="length">493029</property>
   <property name="eof">pause</property>
   <property name="resource">/home/tuti/Área de trabalho/TestVideo.mkv</property>
   <property name="mlt_service">avformat</property>
   <property name="seekable">1</property>
   <property name="format">3</property>
   <property name="audio_index">1</property>
   <property name="video_index">0</property>
   <property name="vstream">0</property>
   <property name="astream">0</property>
   <property name="kdenlive:id">4</property>
   <property name="kdenlive:clip_type">0</property>
   <property name="kdenlive:file_size">6959502294</property>
   <property name="kdenlive:file_hash">fa02c7ad653f97e3695068d3de2b69bf</property>
   <property name="kdenlive:folderid">-1</property>
   <property name="kdenlive:audio_max1">213</property>
  </chain>
 </bin>
 <groups>[
    {
        "data": "2:184422",
        "leaf": "clip",
        "type": "Leaf"
    }
]
</groups>
</kdenlive-scene>

Well it is not a random string, it is the data required for Kdenlive to process a copy/paste operation, and will show up in the clipboard after you do a copy operation in Kdenlive. What is your point regarding this?

(In reply to Jean-Baptiste Mardelle from comment #3)
> Well it is not a random string, it is the data required for Kdenlive to
> process a copy/paste operation, and will show up in the clipboard after you
> do a copy operation in Kdenlive. What is your point regarding this?

So if the user doesn't have a Clipboard history, that string will overwrite their latest text/image copied?
Can't a warning for this be added?

(In reply to Fernando M. Muniz from comment #4)
> So if the user doesn't have a Clipboard history, that string will overwrite
> their latest text/image copied?
> Can't a warning for this be added?

Instead of copying the image/clip from the timeline, Kdenlive copies (or generates?) that string. Like any other copy operation, the content of the clipboard is overwritten by the last copy action. So this works as designed and expected.