While improving some Remarkup aspects and trying to do my self to avoid to build expensive `PhutilURI` objects, I've noticed that the `PhabricatorEnv#isSelfURI()` does not have a cache at the moment, and it always rebuilds its internal list of `PhutilURI`, every time you call the method.
https://we.phorge.it/source/phorge/browse/master/src/infrastructure/env/PhabricatorEnv.php;9047e940e0637efdea0bbb19bd9d122edbe8d418$441-442
Unclear where I should tag this. This may be just related to Performance and micro-optimizations.
Suggested unit tests, if you will ever work on this:
```
arc unit ./src/infrastructure/parser/__tests__/PhutilPygmentizeParserTestCase.php
arc unit ./src/infrastructure/markup/remarkup/__tests__/PhutilRemarkupEngineTestCase.php
```