Bugzilla

A few things:
(1) bug 1884424 didn't regress the behavior of this test; it's where we *added this test*.  (And adding the test triggered a `test-verify` run, which apparently experienced some unexpected timeouts on mac, which resulted in this bug.)

(2) It's pretty surprising that this test would timeout, since it's just a static html+css testcase with no scripting or animation or anything; it should just load instantly.

(3) Looking at the log, I think the timeout is something happening in the harness or the environment, possibly before we even attempt to load the test.  Before each test that times out in the log, I see this:
```
Mozilla has caught an Obj-C exception [NSGenericException: *** Collection <__NSArrayM: 0x16304dd60> was mutated while being enumerated.]
```
There are 45 instances of this message in the log here (one for each timeout that happened, I think).

So this seems to be an issue with the harness or environment, not with this test.

--> Unmarking this as a regression from bug 1884424, and reclassifying in the Testing component, tentatively under `web-platform-tests` if this is that harness (or perhaps the associated test-verify machinery).

jmaher, do you know what might be going on here? Maybe something about `test-verify` and the harness is using a `__NSArrayM` under the hood and mutating it as we go?  (Or maybe this was just a one-off, not sure.)

A few things:
(1) bug 1884424 didn't regress the behavior of this test; it's where we *added this test*.  (And adding the test triggered a `test-verify` run, which apparently experienced some unexpected timeouts on mac, which resulted in this bug.)

(2) It's pretty surprising that this test would timeout, since it's just a static html+css testcase with no scripting or animation or anything; it should just load instantly.

(3) Looking at the log, I think the timeout is something happening in the harness or the environment, possibly before we even attempt to load the test (though it ends up [mistakenly?] getting attributed to the test).  Before each test that times out in the log, I see this:
```
Mozilla has caught an Obj-C exception [NSGenericException: *** Collection <__NSArrayM: 0x16304dd60> was mutated while being enumerated.]
```
There are 45 instances of this message in the log here (one for each timeout that happened, I think).

So this seems to be an issue with the harness or environment, not with this test.

--> Unmarking this as a regression from bug 1884424, and reclassifying in the Testing component, tentatively under `web-platform-tests` if this is that harness (or perhaps the associated test-verify machinery).

jmaher, do you know what might be going on here? Maybe something about `test-verify` and the harness is using a `__NSArrayM` under the hood and mutating it as we go?  (Or maybe this was just a one-off, not sure.)