wdr.de extractor does not download the subtitle

[ismail]

> youtube-dl -v --list-subs https://www1.wdr.de/mediathek/video/sendungen/quarks-und-co/video-explosives-erbe-blindgaenger-unter-unseren-fuessen-100.html             
[debug] System config: []                                                                                                                                                    
[debug] User config: []                                                                                                                                                      
[debug] Custom config: []                                                                                                                                                    
[debug] Command-line args: ['-v', '--list-subs', 'https://www1.wdr.de/mediathek/video/sendungen/quarks-und-co/video-explosives-erbe-blindgaenger-unter-unseren-fuessen-100.ht
ml']                                                                                                                                                                         
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8                                                                                                             
[debug] youtube-dl version 2019.09.28                                                                                                                                        
[debug] Python version 3.7.3 (CPython) - Linux-5.0.0-17-generic-x86_64-with-Ubuntu-19.04-disco                                                                               
[debug] exe versions: ffmpeg N-50244-ga1e5c35a6e-static, ffprobe N-50244-ga1e5c35a6e-static                                                                                  
[debug] Proxy map: {}                                                                                                                                                        
[WDRPage] video-explosives-erbe-blindgaenger-unter-unseren-fuessen-100: Downloading webpage                                                                                  
[download] Downloading playlist: video-explosives-erbe-blindgaenger-unter-unseren-fuessen-100                                                                                
[WDRPage] playlist video-explosives-erbe-blindgaenger-unter-unseren-fuessen-100: Collected 1 video ids (downloading 1 of them)                                               [download] Downloading video 1 of 1                                                                                                                                          
[debug] Using fake IP 53.154.3.191 (DE) as X-Forwarded-For.                                                                                                                  
[WDR] 2003676: Downloading JSON metadata                                                                                                                                     
[WDR] 2003676: Downloading m3u8 information                                                                                                                                  
[WDR] 2003676: Downloading m3u8 information                                                                                                                                  
mdb-2003676 has no subtitles                                                                                                                                                 
[download] Finished downloading playlist: video-explosives-erbe-blindgaenger-unter-unseren-fuessen-100 

The subtitle track is in the page:

<track id="videoPlayerTextTrack" kind="subtitles" srclang="de" label="Deutsch - WDR" default="" src="blob:https://www1.wdr.de/a92c7b9e-ebbf-4cff-af36-846bd44c59d3">