youtube-dl NOT providing valid JSON content when using dump-json option (do NOT close without addressing, please)

[soapstreams]

Checklist

• I'm reporting a broken site support
• I've verified that I'm running youtube-dl version 2019.11.05
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that all URLs and arguments with special characters are properly quoted or escaped
• I've searched the bugtracker for similar issues including closed ones

Verbose log

login as: root
root@94.102.59.20's password:
Last failed login: Tue Nov 12 23:38:43 EST 2019 from 112.85.42.89 on ssh:notty
There were 423 failed login attempts since the last successful login.
Last login: Tue Nov 12 21:02:56 2019 from 89.187.175.23
[root@soappirat ~]# youtube-dl --version
2019.11.05
[root@soappirat ~]# youtube-dl -v https://www.youtube.com/watch?v=KSBGBd9IY0U&list=PLV-jnXv3eCNOmWsu169vgjCTB92pePa27&index=2&t=37s
[1] 14694
[2] 14695
[3] 14696
[root@soappirat ~]# [debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'-v', u'https://www.youtube.com/watch?v=KSBGBd9IY0U']
[debug] Encodings: locale UTF-8, fs UTF-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2019.11.05
[debug] Python version 2.7.5 (CPython) - Linux-3.10.0-693.2.2.el7.x86_64-x86_64-with-centos-7.7.1908-Core
[debug] exe versions: ffmpeg 2.8.15, ffprobe 2.8.15
[debug] Proxy map: {}
[youtube] KSBGBd9IY0U: Downloading webpage
[youtube] KSBGBd9IY0U: Downloading video info webpage
[youtube] {18} signature length 107, html5 player vflu-qpOO
[youtube] {22} signature length 107, html5 player vflu-qpOO
[youtube] {43} signature length 107, html5 player vflu-qpOO
[youtube] {137} signature length 107, html5 player vflu-qpOO
[youtube] {248} signature length 107, html5 player vflu-qpOO
[youtube] {136} signature length 103, html5 player vflu-qpOO
[youtube] {247} signature length 107, html5 player vflu-qpOO
[youtube] {135} signature length 107, html5 player vflu-qpOO
[youtube] {244} signature length 103, html5 player vflu-qpOO
[youtube] {134} signature length 107, html5 player vflu-qpOO
[youtube] {243} signature length 103, html5 player vflu-qpOO
[youtube] {133} signature length 107, html5 player vflu-qpOO
[youtube] {242} signature length 103, html5 player vflu-qpOO
[youtube] {160} signature length 103, html5 player vflu-qpOO
[youtube] {278} signature length 107, html5 player vflu-qpOO
[youtube] {140} signature length 107, html5 player vflu-qpOO
[youtube] {251} signature length 103, html5 player vflu-qpOO
[youtube] KSBGBd9IY0U: Downloading MPD manifest
[debug] Default format spec: bestvideo+bestaudio/best
WARNING: Requested formats are incompatible for merge and will be merged into mkv.
[debug] Invoking downloader on u'https://manifest.googlevideo.com/api/manifest/dash/expire/1573641868/ei/LIrLXf-1GIbD1wKR776oBg/ip/94.102.59.20/id/29204605df486345/source/youtube/requiressl/yes/playback_host/r5---sn-5hne6nsk.googlevideo.com/mm/31%2C29/mn/sn-5hne6nsk%2Csn-5hnekn7d/ms/au%2Crdu/mv/u/mvi/4/pl/24/hfr/all/as/fmp4_audio_clear%2Cwebm_audio_clear%2Cwebm2_audio_clear%2Cfmp4_sd_hd_clear%2Cwebm2_sd_hd_clear/mt/1573619887/fvip/5/fexp/23842630/itag/0/sparams/expire%2Cei%2Cip%2Cid%2Csource%2Crequiressl%2Chfr%2Cas%2Citag/sig/ALgxI2wwRAIgRSu6JMJ-MJ9mBJPP2xBxOWfVP-F0m0_M6ijnQNgEe-oCIE1CvbXPp9nAbVokRzJ22hiFwwUFI-2JAMSfGq2M3Pk2/lsparams/playback_host%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl/lsig/AHylml4wRAIgD5GZhqnNM3tnCCdMJyEMnFz6z8jx85Kk2o-R-ib_1xcCIDGYH_MQhRd5M_KYNmde3cclCfcNSihOabxO3mmGYVlr'
[dashsegments] Total fragments: 503
[download] Destination: Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.f137.mp4
[download]  60.4% of ~552.56MiB at 15.67MiB/s ETA 00:48^C
[2]-  Done                    list=PLV-jnXv3eCNOmWsu169vgjCTB92pePa27
[3]+  Done                    index=2
[download] 100% of 551.69MiB in 02:51
[debug] Invoking downloader on u'https://manifest.googlevideo.com/api/manifest/dash/expire/1573641868/ei/LIrLXf-1GIbD1wKR776oBg/ip/94.102.59.20/id/29204605df486345/source/youtube/requiressl/yes/playback_host/r5---sn-5hne6nsk.googlevideo.com/mm/31%2C29/mn/sn-5hne6nsk%2Csn-5hnekn7d/ms/au%2Crdu/mv/u/mvi/4/pl/24/hfr/all/as/fmp4_audio_clear%2Cwebm_audio_clear%2Cwebm2_audio_clear%2Cfmp4_sd_hd_clear%2Cwebm2_sd_hd_clear/mt/1573619887/fvip/5/fexp/23842630/itag/0/sparams/expire%2Cei%2Cip%2Cid%2Csource%2Crequiressl%2Chfr%2Cas%2Citag/sig/ALgxI2wwRAIgRSu6JMJ-MJ9mBJPP2xBxOWfVP-F0m0_M6ijnQNgEe-oCIE1CvbXPp9nAbVokRzJ22hiFwwUFI-2JAMSfGq2M3Pk2/lsparams/playback_host%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl/lsig/AHylml4wRAIgD5GZhqnNM3tnCCdMJyEMnFz6z8jx85Kk2o-R-ib_1xcCIDGYH_MQhRd5M_KYNmde3cclCfcNSihOabxO3mmGYVlr'
[dashsegments] Total fragments: 269
[download] Destination: Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.f251.webm
[download] 100% of 31.96MiB in 01:23
[ffmpeg] Merging formats into "Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.mkv"
[debug] ffmpeg command line: ffmpeg -y -loglevel 'repeat+info' -i 'file:Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.f137.mp4' -i 'file:Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.f251.webm' -c copy -map '0:v:0' -map '1:a:0' 'file:Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.temp.mkv'
Deleting original file Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.f137.mp4 (pass -k to keep)
Deleting original file Santa Barbara, Ep# 1   M073084-KSBGBd9IY0U.f251.webm (pass -k to keep)

[1]+  Done                    youtube-dl -v https://www.youtube.com/watch?v=KSBGBd9IY0U
[root@soappirat ~]# https://www.youtube.com/watch?v=KSBGBd9IY0U&list=PLV-jnXv3eCNOmWsu169vgjCTB92pePa27&index=2&t=37s

Description

WRITE DESCRIPTION HERE

I have a site (soappirat.es) that uses Kernel Video Sharing (KVS) script. When I try to import a video using the KVS YouTube Grabber plugin, the log reports the following error: "ERROR: video page gives unexpected error:Invalid response from youtube-dl."

When I emailed KVS support about the issue, I was told it was a youtube-dl bug. When I use youtube-dl from the command line using the "-v" flag--you see the output above. According to KVS: "It indeed works in download mode, but doesn't provide valid JSON content when using --dump-json option. KVS grabbers work in 2 steps, they first analyze the parsed info to identify whether the parsed video is OK, then start downloading it. This particular video fails during the 1st phase. The created JSON is not valid and can't be parsed, e.g. you can see that when you open it with Firefox for example, which has built-in JSON parser.
If this issue is fixed in youtube-dl, KVS grabber should work fine."

I tried to run youtube-dl -v --dump-json [youtube URL], but the output exceeds my command windows capacity to hold it all.

jdr