Extension load fails in COI mode

[jheer]

What happens?

I'm trying to use the coi mode to enable multiple threads. While initialization and basic queries work, I'm seeing errors when attempting to ingest a Parquet file due to a failure of extension loading. The error does not occur in other modes (eh is fine).

I realize coi mode is still experimental, but it would be great to take advantage of parallelism and still have access to the core extensions.

To Reproduce

• Configure server to provide COI headers.

  headers: {
     'Cross-Origin-Embedder-Policy': 'require-corp',
     'Cross-Origin-Opener-Policy': 'same-origin',
   }
  

• Load DuckDB-WASM using coi bundle.
• Initialize an AsyncDuckDB instance, create a new connection conn.
• Issue the following query:

  conn.query(`CREATE TABLE flights AS SELECT * FROM 'https://idl.uw.edu/mosaic-datasets/data/flights-10m.parquet'`)
  

The query triggers automatic loading of the parquet extension, which fails with the following errors.

In Chrome:

Error: Extension Autoloading Error: An error occurred while trying to automatically install the required extension 'parquet':
Extension "https://extensions.duckdb.org/v1.3.0/wasm_threads/parquet.duckdb_extension.wasm" could not be loaded: Could not load dynamic lib: parquet
LinkError: WebAssembly.Instance(): Import #4582 "env" "memory": mismatch in shared state of memory, declared = 0, imported = 1
    at AsyncDuckDB.onMessage (async_bindings.ts:160:23)

In Firefox:

Error: Extension Autoloading Error: An error occurred while trying to automatically install the required extension 'parquet':
Extension "https://extensions.duckdb.org/v1.3.0/wasm_threads/parquet.duckdb_extension.wasm" could not be loaded: Could not load dynamic lib: parquet
LinkError: imported shared memory but unshared required

Browser/Environment:

Chrome 136.0, Firefox 136.0.2

Device:

MacBook

DuckDB-Wasm Version:

1.29.1-dev207.0; 1.29.0

DuckDB-Wasm Deployment:

coi mode in browser

Full Name:

Jeffrey Heer

Affiliation:

University of Washington

[jheer]

FWIW, I subsequently tested a number of other extensions: json, spatial, icu, excel, etc. All fail with the same error. Another way to replicate the problem is to simply run conn.query('INSTALL json; LOAD json;').