bts-downloader

A BlockTheSpot mod for the experimental loader (bts-loader.dll). It changes two Remote Config defaults that the Spotify desktop client consults around downloads and the offline content capability.

This is not a patcher, not a client, and not a downloader implementation. It is a declarative INI mod that the loader's patch engine applies to the app bundle, the same way BlockTheSpot applies its own frontend patches.

• Target: Spotify 1.3.1.234 x64 (the version the experimental branch targets)
• Loader: patches/ in BlockTheSpot's experimental layout
• Format: standalone INI mod, no DLL, nothing to compile

What it changes

[Buffer_modify] names one SPA file, pip-mini-player-snapshot.js, and attaches two patch groups:

group	edit
enableContentCapabilityEpisodeDownload-1	default:!1 → default:!0
enableRemoteDownloads-2	default:!1 → default:!0

Both are equal-length byte swaps inside the flag definitions. The loader's engine rejects a replacement longer than its signature, so this is the only kind of edit a declarative mod can express.

Precedence matters: the client resolves a property as local override → server value → default. This mod changes the default. If the server sends a value for either property, the server wins. The mod API (v2) exposes register_ini and logging only — no override or memory API — so the fallback is the developer menu the experimental build enables: Develop → Show debug window → Remote Config. A local override set there does outrank the server value.

Install

1. Have the experimental BlockTheSpot loader installed: the chrome_elf.dll proxy, bts-loader.dll and config.ini in %APPDATA%\Spotify, with a patches\ directory next to them.
2. Copy spdl-offline.ini into %APPDATA%\Spotify\patches\.
3. Quit Spotify completely, including the tray icon, and start it again.
4. Read blockthespot-status.txt. Expect Mod spdl-offline.ini with ready, and one row per patch target at ready or applied.

Optional validation, if patch-tool.exe ships with your loader build:

.\out\tools\patch-tool.exe inspect-mod .\patches\spdl-offline.ini

skipped or failed in the status file means the bytes did not match your build. Regenerate — do not hand-edit the hex.

Verify by observation, not by the UI

• Press download on a track.
• Watch for storage-resolve/v2/files/audio/offline/… in the client's traffic.
• Watch %LOCALAPPDATA%\Spotify\Storage\ for new files.
• In the debug window, confirm the property's localValue / remoteValue actually changed; rows that differ from the default are flagged.

If the control appears but no resolve request fires, the gate is server-side and no local edit moves it.

Rebuild for another build

Signatures embed the flag's description text, and the file name must match the zip entry, so the mod is build-specific. tools/make-bts-pack.py regenerates it from an unpacked xpui.spa:

python3 tools/make-bts-pack.py xpui --list

python3 tools/make-bts-pack.py xpui enableContentCapabilityEpisodeDownload enableRemoteDownloads --to true --mod --version 1.3.1.234 > mod/spdl-offline.ini

On Windows the bundle lives at %APPDATA%\Spotify\Apps\xpui.spa. Use the version the loader reports for your client in [Compatibility].

Repository layout

mod/spdl-offline.ini        the mod
tools/make-bts-pack.py      generator (--list, --mod, --version)
tools/validate_mod.py       CI check: sections, hex, equal-length rule
.github/workflows/release.yml   validate, package, publish

Releases

Every push to main validates the mod and, if it passes, creates a release tagged v<date>-<short sha> with spdl-offline.zip and the raw spdl-offline.ini.

Status

The current signatures were generated from the 1.3.1.234 app bundle. They have not been loaded by bts-loader.dll on a Windows client. Treat this as experimental: check blockthespot-status.txt before drawing conclusions, and regenerate per build.

Disclaimer

This project is not affiliated with, endorsed by, or sponsored by Spotify AB or the BlockTheSpot project. "Spotify" is a trademark of Spotify AB. No Spotify binary is redistributed here; the mod contains configuration that a third-party loader applies to a client you already have installed.

If you are a rights holder, a maintainer, or anyone with a concern about this repository, please open an issue or reach the maintainer through the GitHub profile before taking any other action. We will respond and remove material where appropriate.

License

Apache-2.0. See LICENSE. The license covers this repository's own files; it grants nothing in respect of Spotify's software or BlockTheSpot, which are governed by their own terms.