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Co-authored-by: Ivan <[email protected]>

js/tc39/README.md

@@ -1,14 +1,14 @@
 # Introduction to a k6's TC39 testing
 
-This module tests k6 [Sobek](https://github.com/grafana/sobek) and the k6 Sobek+esbuild combo against the tc39 test suite.
+`js/tc39` package tests k6 [Sobek](https://github.com/grafana/sobek) and the k6 Sobek+esbuild combo against the tc39 test suite.
 
 Ways to use it:
 1. run ./checkout.sh to checkout the last commit sha of [test262](https://github.com/tc39/test262)
    that was tested with this module
 2. Run `go test &> out.log`
 
 The full list of failing tests, and the error, is in `breaking_test_errors-*.json`. All errors list there with the corresponding error will *not* be counted as errors - this is what the test expects, those specific errors.
-Due to changes to Sobek it is not uncommon for the error to change, or there to be now a new error on previously passing test, or (hopefully) a test that was not passing but now is.
+Due to changes to Sobek it's common for the error to change, or there to be now a new error on the previously passing test, or (hopefully) a test that was not passing but now is.
 In all of those cases `breaking_test_errors-*.json` needs to be updated. Run the test with `-update` flag to update: `go test -update`
 
 NOTE: some text editors/IDEs will try to parse files ending in `json` as JSON, which given the size of `breaking_test_errors-*.json` might be a problem when it's not actually a JSON (before the edit). So it might be a better idea to name it something different if editing by hand and fix it later.
@@ -27,6 +27,6 @@ This also means that, if the
 previous breakage was something a user can work around in a certain way, it now might be something
 else that the user can't workaround or have another problem.
 
-Starting v0.53 k6 doesn't use babel, it is mostly for testing esbuild, but also due to Sobek not testing a lot more stuff. It is still possible that we drop this whole package in the future.
+Starting v0.53 k6 doesn't use Babel anymore, it now serves tests for `esbuild`, and for the parts uncovered by Sobek's test suite. It is still possible that we drop the whole package in the future.
 
 For these reasons, I decided that recording what breaks and checking that it doesn't change is better.

lib/runtime_options.go

@@ -13,9 +13,9 @@ import (
 type CompatibilityMode uint8
 
 const (
-	// CompatibilityModeExtended adds global as alias for globalThis on top of the base
+	// CompatibilityModeExtended adds `global` as an alias for `globalThis` on top of the base mode
 	CompatibilityModeExtended CompatibilityMode = iota + 1
-	// CompatibilityModeBase is standard Sobek
+	// CompatibilityModeBase is standard Sobek, which means pure vanilla JS following ECMAScript standards.
 	CompatibilityModeBase
 	// CompatibilityModeExperimentalEnhanced achieves TypeScript and ES6+ compatibility with esbuild
 	CompatibilityModeExperimentalEnhanced