Export used in unknown ways

Index.js

compiler.hooks.thisCompilation.tap(
  "FlagEntryExportAsUsedPlugin",
  compilation => {
    const moduleGraph = compilation.moduleGraph;
    compilation.hooks.seal.tap("FlagEntryExportAsUsedPlugin", () => {
      for (const deps of compilation.entryDependencies.values()) {
        for (const dep of deps) {
          const module = moduleGraph.getModule(dep);
          if (module) {
            const exportsInfo = moduleGraph.getExportsInfo(module);
            if (this.nsObjectUsed) {
              // mark that exports are used in an unknown way, preventing tree-shaking on a file or module 
              exportsInfo.setUsedInUnknownWay();
            } else {
              exportsInfo.setAllKnownExportsUsed();
            }
            moduleGraph.addExtraReason(module, this.explanation);
          }
        }
      }
    });
  }
);