<p>Right but it's the phantomjs executable that's missing - the gem is just a bit of ruby that tries to figure out what platform it is running on and then use curl to download a suitable executable.</p>
<p>In can well imagine that docker is confusing it's attempt to identify the platform, or perhaps you don't have curl installed, or the network access isn't working - try looking for error messages as it tries to download and install phantomjs.</p>
<p>It's probably better to install phantomjs yourself if you can - it will probably be more reliable.</p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">—<br />You are receiving this because you are subscribed to this thread.<br />Reply to this email directly, <a href="https://github.com/openstreetmap/openstreetmap-website/issues/1931?email_source=notifications&email_token=AAK2OLN7KEO37DHODCNFFSLQASCWNA5CNFSM4FLH7J22YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD2OGREY#issuecomment-513566867">view it on GitHub</a>, or <a href="https://github.com/notifications/unsubscribe-auth/AAK2OLKF552QPRV54UXVN63QASCWNANCNFSM4FLH7J2Q">mute the thread</a>.<img src="https://github.com/notifications/beacon/AAK2OLIKEWDPL3IE2D4XL6LQASCWNA5CNFSM4FLH7J22YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD2OGREY.gif" height="1" width="1" alt="" /></p>
<script type="application/ld+json">[
{
"@context": "http://schema.org",
"@type": "EmailMessage",
"potentialAction": {
"@type": "ViewAction",
"target": "https://github.com/openstreetmap/openstreetmap-website/issues/1931?email_source=notifications\u0026email_token=AAK2OLN7KEO37DHODCNFFSLQASCWNA5CNFSM4FLH7J22YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD2OGREY#issuecomment-513566867",
"url": "https://github.com/openstreetmap/openstreetmap-website/issues/1931?email_source=notifications\u0026email_token=AAK2OLN7KEO37DHODCNFFSLQASCWNA5CNFSM4FLH7J22YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD2OGREY#issuecomment-513566867",
"name": "View Issue"
},
"description": "View this Issue on GitHub",
"publisher": {
"@type": "Organization",
"name": "GitHub",
"url": "https://github.com"
}
}
]</script>