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# Visual Tests
Visual tests are typically used when testing rendering of things that
cannot be tested with [reftests](reftests).
Their main advantage of over manual tests is they can be verified using
browser-specific and platform-specific screenshots; note, however, that many
browser vendors treat them identically to manual tests hence they are
similarly discouraged as they very infrequently, if ever, get run by them.
## Writing a Visual Test
Visuals tests are test files which have `-visual` at the end of their
filename, before the extension. There is nothing needed in them to
make them work.
They should follow the [general test guidelines](general-guidelines),
especially noting the requirement to be self-describing (i.e., they
must give a clear pass condition in their rendering).
Similarly, they should consider the [rendering test guidelines](rendering),
especially those about color, to ensure those running the test don't
incorrectly judge its result.
The screenshot for comparison is taken at the same point as when screenshots
for [reftest comparisons](reftests) are taken, including potentially waiting
for any `class="reftest-wait"` to be removed from the root element.