The common code for content scripts and sidepanel is not shared (e.g., React).

Feature Request

My extension has three entry points: two content scripts and one sidepanel. All use React, but after packaging, I found that React was not extracted into a shared module, resulting in a larger installation package size.

Is your feature request related to a bug?

It may be related to #357, but it does not meet my expectations.

It achieves code splitting by dynamically loading esm within the content script, but this causes run_at to fail. What I want is to achieve code sharing by changing all output formats to a unified iife.

What are the alternatives?

I suspect this may be due to the different export formats: the content script is iife, while the sidepanel is esm.

Would exporting both to the iife format allow Rollup to generate shared code chunks normally?

Additional context

I am currently converting an extension I have already developed to use WXT. Previously, I used Webpack, my strategy was to bundle the background script separately and then bundle all other parts together; WXT's strategy seems to be to bundle the content script separately, which led to the issue I'm raising.

The installation package size I originally generated using Webpack was 412 KB, but after switching to WXT, it increased to 633 KB.

Start by tracing how the content-script and sidepanel entry points are bundled and compare their current IIFE and ESM outputs. Check whether a shared React module can be produced without breaking content-script run_at behavior; done means the packaged extension shares common code and avoids the reported size increase.