It would be great if this program could download all parts with just selcet and copy like jdownloader2, i use some site who is sometimes with 2 part or more but i must copy past all the links to program to download them. it could be big help for many ppl.

Do you mean something like "Download selected" in the context menu?

i mean i use this site https://igg-games.com/ and download the game (exaple: https://igg-games.com/devil-may-cry-5-p ... nload.html) if this game work fine before i bought them and its annoing when i must go in browser too all paty to the point i will see on browser the link from megaup or other servers. In Jdownloader2 is possible just select part 1,2,3.... and the downloader can download the files. I dont know if u understend me but i hope just a liitle.

You can use "Download selected with FDM" for direct download links, otherwise there is no guarantee the links will be properly redirected.
As it is with many file hosting sites, there are no direct download links there. It depends on the server side which link will be redirected to what webpage. If you had saved your credentials for the download site in the browser, you may be redirected to download link, otherwise you may see login page, page with CAPTCHA, page with warning about adblock in use, etc. or simply "404 Page not found" error page.
FDM is a standalone program, its extension must pass the download link and cookies outside the browser to the program which keeps credentials separately in its own database. JDownloader is a Java applet working inside the browser - it has easier job to do, it may follow redirections in a less visible way, yet it may also get stuck on some redirections.

There's one more problem: File hosting sites allow only one download at a time for free account users. The sites generate temporary download links, so you cannot get all the links once and queue them - they will expire before you finish downloading the first part. Only you can decide which part to download from which site if you want to start downloading more parts at a time - it's a manual job, but you will get your download faster.

CooperPL ver2 wrote:i mean i use this site https://igg-games.com/ and download the game (exaple: https://igg-games.com/devil-may-cry-5-p ... nload.html) if this game work fine before i bought them and its annoing when i must go in browser too all paty to the point i will see on browser the link from megaup or other servers. In Jdownloader2 is possible just select part 1,2,3.... and the downloader can download the files. I dont know if u understend me but i hope just a liitle.

Usher described the situation very well, it's pretty much a different process from what FDM normally offers.