After updating to Firefox "quantum" all text on most webpages is gone or show as small squares.    The issue occurs on most websites including google, askubuntu.com and the built in firefox new tab page. It does not occur on mozilla.org or a few other sites I've randomly tested.  Starting Firefox from terminal yields this error message:   (/usr/lib/firefox/firefox:3897): Pango-WARNING **: failed to create cairo scaled font, expect ugly output. the offending font is 'Ubuntu 11' (/usr/lib/firefox/firefox:3897): Pango-WARNING **: font_face status is: file not found (/usr/lib/firefox/firefox:3897): Pango-WARNING **: scaled_font status is: file not found (/usr/lib/firefox/firefox:3897): Pango-WARNING **: shaping failure, expect ugly output. shape-engine='PangoFcShapeEngine', font='Ubuntu 11', text='●'   EDIT:  This appears to be caused by the combination of having fonts stored in a non-default location (on a separate drive from my OS) and  bug in firefox 57.
After upgrading to Firefox 57 Quantum many website have rendering issues, such as empty frames, missing text or fonts, etc. I use Kubuntu 16.04 64 bit.  So far, I've tried:   Restarting Firefox in safe mode Disabling "hardware acceleration"   Wiping out my profile Purging Firefox and reinstalling Running Firefox from a clean user account   But nothing helped so far.  Any tips on how to solve this are much appreciated
Where were the Avengers during Iron Man 3? Transferring Money from India Upload images from the Stack Exchange Android app I would like to request implementation of uploading images to questions/answers from the Stack Exchange Android app, especially now as it would definitely help uploading screenshots for reporting bugs and feature requests. I'm interested in quantum mechanics book that uses high level mathematics (not only the usual functional analysis and the theory of generalised functions but the theory of pseudodifferential operators etc, certainly the modern mathematics). If there isn't something similar please give me a reference to the book that is strictly supported by mathematics (given a set of mathematically descripted axioms author develops the theory using mathematics as a main tool). Deleted posts should not influence reputation If I upgrade Ubuntu 12.04 to 14.04, will NS2 still be supported?  I am currently using NS2 on Ubuntu 12.04. New global preferences: keyboard shortcuts and sticky topbar Following a global preference for , as of now, the preferences for enabling keyboard shortcuts and disabling the fixed topbar are network-wide* as well.  If you had either checked off on any site in the network, that setting has been preserved and applied to the whole network for your account already. Future changes will also apply to all* Q&amp;A sites.  Find them in their usual spot as previously on the  pages.    * With the exception of , which will support the fixed topbar after the . Aliens abduct mathematician, astronomer, woman Bits I remember about this SF movie which probably originated in late 50s / early 60s:   Humans are flying in a light, general aviation, high winged, single engine aircraft. An alien in a flying saucer abducts the whole kit &amp; kaboodle (plane &amp; passengers). Takes them to a secret terrestrial base Eventually tells them that his computer is damaged and he needs their help to get back to his planet. He needs an astronomer for planetary masses &amp; other information. He needs a mathematician to calculate trajectories and perform other calculations. He needs the woman as eye candy, lol They eventually make it back to the alien home planet which is under attack by its enemy. The attacking aliens are bombarding the original alien's home planet with meteors / asteroids.   That's about all I remember. Rigorously proving equal tension on both ends There is always one point in introductory mechanics that has been continuously bothering me ever since I had taken my freshman physics course - Why does a massless rope have its tension equal on both ends?  I have been searching for a good explanation on various textbooks at different levels, but none of them provided me a satisfactory explanation. They either   State directly "we assume the string is massless and the pulley has no friction, therefore the tension must be the same throughout the string" without further any elaboration and continue the calculation, Claim without any reasons that "whenever the rope and the pulley are massless and frictionless, the tension will be the same on both sides", or Explain using a lot of hand-waving arguments regarding infinite acceleration, non-zero moment of inertia, etc. , in one line or two.   Although those hand-waving arguments of type $(3)$ do sound quite reasonable to me and will convince me for a while every time I review them. But after a while, I will start feeling not well about this whole tension concept again.  Therefore, I am looking for a rigorous (in the physicist's sense) proof of exactly why and when do the tension in rope will be uniform, and hopefully from that I can clean up all of my conceptual difficulties. Could I use a 1/2TB USB 2/3 external HDD with an XBox 360? Calculating sequential numbers into sorted table using ArcGIS Desktop? Emboss text onto curved surface I am fairly new to blender and I am trying to do something which I am assuming is fairly straight forward with no success. All I'm looking to do is emboss some text onto the curved part of a yogurt pot. Image attached below. What is the quickest and easiest way of doing this?  Thanks in advance If $A$ is a square matrix and $A^2 = 0$ then $A=0$. Is this true? If not, provide a counter-example. Conjugate to $\cos z$ is not equal to $\cos z$ conjugate $\overline{\cos(z)}\neq\cos(\overline{z})$ I have a dilemma. I have a task where I'm supposed to show that $|\cos z|^2+|\sin z|^2=1$ if and only if $z\in \mathbb{R} $. In my argument I have that $$\cos z\cdot\overline{\cos z} + \sin z\cdot\overline{\sin z}=\cos z\cdot \cos\overline{z} + \sin z\cdot \sin\overline{z}$$ but my teacher said that $\overline {\cos z} \neq \cos \overline{z}$.  Is this true?  But $$\overline{\cos(z)} = \overline{\frac{e^{iz}+e^{-iz}}{2}}=\frac{e^{-i\overline{z}}+e^{i\overline{z}}}{2}=\cos(\overline{z})$$ Is it possible to get a list of most recently installed packages? Some doubts about photons What is the formula for this numerical series? How do I tell what gauge wire I need? I've been working on providing power for high current applications for my project. I'm working on a project with high current (or at least compared to what I'm used to...)  What a lot of people point to online is tables that you can look up the resistance for AWG per foot, and then you can calculate the current drop of your wire. However, with that current drop, how much of  a voltage drop will make my wire "too hot" and risk a fire? Am I looking at this the wrong way? How do I calculate the temperature of the wire and decide when it'll be too hot, and I should use a thicker wire? How do I handle the window close event in Tkinter? In $\mathbb{Z}/(n)$, does $(a) = (b)$ imply that $a$ and $b$ are associates? [Update: Based on the hints provided by @zcn and @whacka, I believe I have found a solution. See my answer below.]  Below, $R$ is a commutative ring with $1$.  In John J. Watkins' Topics in Commutative Ring Theory, the author observes that if $a$ and $b$ are associates in $R$, then they generate the same ideal: $(a) = (b)$. This is clearly true, because $a = ub$ and $b = va$ for some units $u$ and $v$, and so $a \in (b)$ and $b \in (a)$, whence $(a) \subset (b)$ and $(b) \subset (a)$. Indeed, we didn't even require $u$ and $v$ to be units to reach this conclusion.  The author then claims that if $R$ is not a domain, then the converse may not be true: we may have $(a) = (b)$ even if $a$ and $b$ are not associates. As a "counterexample" he gives $R = \mathbb{Z}/(6)$, with $a = 2 + (6)$ and $b = 4 + (6)$. Clearly these elements generate the same ideal: $(a) = (b) = \{0, 2 + (6), 4 + (6)\}$. The author asserts that $a$ and $b$ are not associates, but this is false: $5 + (6)$ is a unit, and $(2 + (6))(5 + (6)) = 4 + (6)$, so $a$ and $b$ actually are associates.  I figured that the author botched the example but that surely the basic fact must be true: if $R = \mathbb{Z}/(n)$ then there may be nonassociates $a,b \in R$ with $(a) = (b)$. However, I was not able to find a counterexample and eventually resorted to writing a computer program and found that there are no counterexamples in $\mathbb{Z}/(n)$ for $n \leq 100$.  So now I'm starting to think that there is no counterexample in $\mathbb{Z}/(n)$ at all, but I have not yet been able to prove this.  My questions:   If I am correct that $(a) = (b)$ in $\mathbb{Z}/(n)$ implies that $a$ and $b$ are associates, I would appreciate a nudge in the right direction toward a proof. (But if the proof is elementary, please give only a hint, not a solution :-) I'll post my solution once I have one. In either case, could you please point me to a genuine counterexample? If there is one in $\mathbb{Z}/(n)$ for some $n$, that would be ideal (no pun intended), otherwise a counterexample in any commutative ring with $1$ would be great.