Server Resource pack and Autojoin to Server

By autojoin, do you mean the game automatically connects to the server upon launching, without going to the main menu? Or something else?

Yes - the game automatically connects to the server at startup,
without going to the main menu,
with these client arguments --server --port, and does not load the serverpack.

When you log on to the server through the main menu, the saved server-side texture packs work fine.

For me it crashes (see MC-109340). Is your client or your server modified in any way (e.g. Forge, Bukkit, Spigot)?

Forge and Spigot and my client not crashed )

Thank you for your report!
However, this issue is Invalid.

Your game, launcher or server is modified.
If you can reproduce the issue in a vanilla environment, please recreate the issue.

• Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang.

• Any plugin issues need to be addressed to the creator of the plugin or resource pack.

• If you have problems on large servers, such as The Hive and Hypixel, please contact them first as they run modified server software.

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Non modifed client getiing crashed
java.lang.NullPointerException: Updating screen events
at bsf.b(SourceFile:92)
at brz$1$1.a(SourceFile:1477)
at bkq.a(SourceFile:50)
at blk.a(SourceFile:337)
at blk.k(SourceFile:400)
at blk.q(SourceFile:377)
at bib.t(SourceFile:1625)
at bib.az(SourceFile:1000)
at bib.a(SourceFile:419)
at net.minecraft.client.main.Main.main(SourceFile:123)

Non modifed client getiing crashed

... but the server is still modified?

i testing it with few variants, in all variants have a some problems
yes i using bungeecord spigot and vanilla(non modifed) .
and i using clients : vanilla , forge , liteloader, optifine and combined variants.
ex. errors crashing, not working resourcepack and Constant pop-up message about loading resourcepack

Reopening after internal discussion (confusion about whether or not it's modded), though also we've decided that this is a duplicate of MC-109340 (stacktraces seem to match).