Cannot continue downloading modpack on missing mod

[Oididoi]

• I searched the issue tracker for other issues covering my case
• This is a Launcher issue. (Usually if you can reproduce it with a fresh instance)

Describe the bug
Once a mod throws back a 404 error, the modpack install can't continue. The only options are to retry or delete the instance.

Iris Shaders for Fabric on 1.19.2 were removed from Curseforge and moved to Modrinth. They can be downloaded manually and added to the instance, but the launcher won't allow that since I can't complete the initial install without the one missing mod.

To Reproduce
Steps to reproduce the behavior:

1. Go to Add New Instance
2. Add any modpack with a mod that has a mod or mod version that isn't currently available on Curseforge (All of Fabric 6 in this instance)
3. Close the 404 error message window that pops up
4. You are presented with two options: retry or delete instance

Possible solutions
The client should skip any mods that aren't found and allow for downloading the rest of the mods, then send a message about the mods that weren't downloaded. Also if Modrinth support were adding this could get around this particular mod not downloading issue.

Operating System:

• OS: Windows 11
• Launcher Version: 1.1.30
• Java Version: 17
• Minecraft Version: 1.19.2
• Mod Loader: Fabric

[skorpeyon]

Happened to me as well today, same specs except that I was attempting to install a modpack for 1.20.1. Tried installing Fabulously Optimized, but since Sodium is no longer on Curseforge, closing out the browser window made the entire install fail instead of just completing and allowing me to manually add Sodium from Modrinth.

[v3m0ch1]

Having the same issue with many different modpacks that use Creatures From The Snow, I assume it's been moved to modrinth as well and now none of these modpacks will install as this one mod throws a 404 and fails the entire pack.

[Oididoi]

@Eskaan @killpowa This is blocking the download of almost any fabric based modpacks since Sodium and Iris Shaders are in the vast majority of them.