The media uploader is not working custom post-types.
Eg. -
https://www.civilsdaily.com/question/temperature-and-vegetation-in-any-region-of-earth-is-governed-by-multiple-factors-latitude-and-altitude-being-the-prominent-ones-comment/&source=gmail&ust=1561282233954000&usg=AFQjCNG4ryrIcMD1wKrbYdXiygs5Tjis1 Q"> https://www.civilsdaily.com/question/temperature-and-vegetation-in-any-region-of-earth-is-governed-by-multiple-factors-latitude-and-altitude-being-the-prominent-ones-comment/
but it is working on normal posts https://www.civilsdaily.com/17th-june-2019-daily-answer-writing-enhancement/
The default implementation should be that it works everywhere where wpdiscuz comment system is available.
An add-on could be a feature to enable/disable uploader on specific custom-post types. This is something that is not required though.
