As a developer, I want to be able to run the browser tests of the Wikidata Query UI, to make sure that they still work.
**Problem:**
Currently, @noarave and I are unable to run the browser tests, and I’m not aware of anyone else being able to run them, either. (Note that we already don’t run them in CI, see T222200.) [According to this Gerrit comment](https://gerrit.wikimedia.org/r/c/wikidata/query/gui/+/604484/2#message-58b8f517a6ee6d22d5912413ba249a2625e222e8), I was still able to run them in June 2020.
**Example:**
```
12:29:10.639 INFO [GridLauncherV3.parse] - Selenium server version: 3.141.59, revision: e82be7d358
12:29:10.744 INFO [GridLauncherV3.lambda$buildLaunchers$3] - Launching a standalone Selenium Server on port 4444
2020-11-06 12:29:10.814:INFO::main: Logging initialized @400ms to org.seleniumhq.jetty9.util.log.StdErrLog
Execution of 1 spec files started at 2020-11-06T11:29:11.019Z
12:29:11.192 INFO [WebDriverServlet.<init>] - Initialising WebDriverServlet
12:29:11.310 INFO [SeleniumServer.boot] - Selenium Server is up and running on port 4444
Selenium started
[0-0] RUNNING in chrome - /tests/specs/embed_spec.js
[0-0] 2020-11-06T11:29:37.103Z ERROR @wdio/runner: Error: connect ECONNREFUSED 127.0.0.1:37695
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1107:14)
[0-0] Error: connect ECONNREFUSED 127.0.0.1:37695
[0-0] FAILED in chrome - /tests/specs/embed_spec.js
Spec Files: 0 passed, 1 failed, 1 total (100% completed) in 00:00:26
```
I tried some combinations of `git bisect` and older Node versions but was unable to find any working state. (On many older Node versions, running the browser tests fails because the `fs-extra` npm package uses `catch {` syntax, which is a syntax error in those versions, so we never even get as far as starting the browser tests proper.)
**Screenshots/mockups:**
**BDD**
GIVEN
AND
WHEN
AND
THEN
AND
**Acceptance criteria:**
* At least one developer on the Wikidata team is able to run the browser tests.
**Open questions:**