i.e. from the "Jessie" (oldstable) distribution; I am not seeing anything from the "Stretch" (stable), "Buster" (testing) or "Sid" (unstable) versions... On the other hand Debian testing does indeed carry Mudlet 3.1 (see https://packages.debian.org/sid/mudlet ).
OTOH that is likely to be shortly disappearing according to my Inbox as I am getting a notification: "mudlet is marked for autoremoval from testing" with the following message body:
mudlet 1:3.7.1-1 is marked for autoremoval from testing on 2018-09-22
It is affected by these RC bugs:
907159: mudlet: FTBFS in buster/sid (invalid use of incomplete type 'class QTabBar')
I tried my hand for a while now at compiling Mudlet for raspi, but I had no luck yet as the precompiled versions of Qt for Raspbian/Debian armhf use OpenGL ES instead of OpenGL (without ES). And that is not compatible with Mudlet. I didn't try to compile Qt myself yet to get it to use the full OpenGL.
TBH I am not sure that you can get the full OpenGL library built on the display hardware that is present in the videocore of any of the RPis - it is the sort of hardware that is going to be targeted by the ES variant. In order to support the lower spec'ed hardware (compared to a Desktop PC) we will really need to update the glwidget class to move away from the simple and fairly straightforward direct OpenGL functions that are a feature of 1.0/1.5/2.0 (and many on-line tutorials) and start using the indirect stuff that 3.0 (and later) OpenGL or OpenGL ES mandates.
Anyone know how to write a shader - SlySven doesn't...