User Agent adjustments

[gmetais]

Hi @macbre,
Yeah, me again...

I've noticed a few issues regarding the user agent sent by Phantomas. By default, Phantomas sends a user agent that looks like Phantomas/2.1.0 (HeadlessChrome/88.0.4298.0). This is OK most of the time.

However, there are some websites that filter users regarding their user agent. You might remember the airline company's website https://www.airfrance.com that was responding with a 403 error (#764). This is not the case when tested with the --phone or the --tablet options, because the user-agent is overridden by Page.emulate().

There is another issue regarding Google Fonts. This service reads user agents to deliver a compatible font format. And when called from Phantomas in desktop mode, it responds with TTF fonts. Example page: https://www.worldelse.com/

I'd like to improve the way it is handled, but we should exchange about the right solution first.

Solution 1:
Change the desktop user agent template, so that it simulates a real Chrome desktop user. For example:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/<ChromiumVersion> Safari/537.36

Solution 1 (extra):
Also change the version for phone and tablet. They seem to be stuck on old browser versions:
Mozilla/5.0 (Linux; Android 5.0; SM-G900P Build/LRX21T) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3765.0 Mobile Safari/537.36
Mozilla/5.0 (Linux; U; en-us; KFAPWI Build/JDQ39) AppleWebKit/535.19 (KHTML, like Gecko) Silk/3.13 Safari/535.19 Silk-Accelerated=true
I do not see it as a problem now, but it could become one if Puppeteer never updates the list. Some websites might trigger a popup saying the device is not supported one day.
We could have a template that auto updates with Chromium's version, just like desktops.

Solution 2:
Allow the user to specify a user-agent. It used to be possible in Phantomas v1, but this option is not working anymore.

Solution 3:
Do all of the above.

[macbre]

@gmetais - thanks for bringing up this topic. I vote for solution 3.

[gmetais]

Ok! Do you want to keep Silk browser for Tablet, or should I replace with Chrome?

[macbre]

Let's use Chrome.