I'm sure others have faced this frustrating issue in the past.   Say you have a dozen tabs open in a browser and you are at a hotel or cafe attempting to use their wifi. You select the wifi ID and all of a sudden, the wifi login screen populates all of your tabs, with no option to go back to the previous website. The content in those tabs has been lost, forever.   How does one prevent this from happening?
It is common for public Wi-Fi access points to include login pages, even at times, when they’re free (i.e. Starbucks, many airports, hotels, etc).  I’m often in a situation where I’ll open up Chrome/Firefox, with and all my previously open tabs will start to reload.  If there is a wireless login redirection page, however, every tab is redirected and reloaded and the previous page is lost from history (and the back button won't return to it).  Is there any way to avoid or circumvent this behavior?
Is the following just a matter of showing the 3 properties that make up a metric??  Define d on $\Bbb R\times\Bbb R$ by $d(x,y)=\min \{1,|x-y|\}$. Show that $d$ is a metric on $\Bbb R$     $d(x,y)=0$ if $x=y$   $d(x,y)=d(y,x)$ for every $x,y \in X$   $d(x,y)\le d(x,z)+d(z,y)$ for every $x,y,z \in X$ I have 2 HDD drives in my computer. At the moment second drive is mounted as /media/storage.  How can I move my user data from /home to /media/storage/home?  Can I just move the data over there and then simply symlink it back? In Iron Man 3, we saw that Tony was able to control Mark 42 armor remotely.  Talking about the Hulkbuster armor used in Avengers: Age of Ultron, it was very dangerous because Hulk's unpredictable rage could rip it apart any time.  Why didn't Iron Man simply control the Hulkbuster armor remotely? LSTM : shape of tensors? What is the physical significance of the off-diagonal moment of inertia matrix elements? The tensor of moment of inertia contains six off-diagonal matrix elements, which vanish if we choose a reference frame aligned with the principal axes of the rotating rigid body; the angular momentum vector is then parallel to the angular velocity. But while considering the general case, what are the off-diagonal moment of inertia matrix elements? That is, do they have any physical significance as [say] the components of a vector? Or is it merely a mathematical construction with no definite physical meaning (which seems rather wrong to me)?  A similar thread exists  but they are more interested in the principal axes of the body. It also says:     The physical significance of the off-diagonal components is that   you're using a coordinate system not aligned with the principal   directions of the object. They tell us nothing interesting about the   object itself.   Is that all or is there more to it, perhaps related to properties of tensors in general? What is "it" in the following sentence: It is clear that Bob likes doughnuts Consider the Fibonacci numbers $F(0) = 0; F(1)=1; F(n) = F(n-1) + F(n-2)$.  Prove by induction that for all $n&gt;0$,  $$F(n-1)\cdot F(n+1)- F(n)^2 = (-1)^n$$  I assume $P(n)$ is true and try to show $P(n+1)$ is true, but I got stuck with the algebra. How do we reach $P(n+1)$ from $P(n)$? Also, strong induction may be used instead. How do I know if a given food or ingredient I have is still good, or if I should discard it?  How can I best preserve a food or ingredient?     This broad question is intended as a "general reference" question to quickly answer many how long will food keep for? questions. Please feel free to edit this question to expand and clarify as needed. Object on curve wont stay flat! Is there a built-in that removes duplicates from list in Python, whilst preserving order? I know that I can use a set to remove duplicates, but that destroys the original order. I also know that I can roll my own like this:  def uniq(input):   output = []   for x in input:     if x not in output:       output.append(x)   return output   (Thanks to  for that .)  But I'd like to avail myself of a built-in or a more Pythonic idiom if possible.  Related question: If I have example.com, and blog.example.com, do search engines see those as one site or two? Will using subdomains hurt SEO? I have some technical reasons why I can't use example.com/blog. When and where can I find the Tower's exotic item vendor (Xur Agent of the Nine)? Why is the following C# code not allowed:  public abstract class BaseClass {     public abstract int Bar { get;} }  public class ConcreteClass : BaseClass {     public override int Bar     {         get { return 0; }         set {}     } }      CS0546 'ConcreteClass.Bar.set': cannot override because 'BaseClass.Bar' does not have an overridable set accessor I want to create a simple figure where images are connected with arrows. Here is what I did:  \begin{tikzpicture} \node[](A) {\includegraphics[width=0.2\textwidth]{a}}; \node[right=1mm of A](B) {\includegraphics[width=0.2\textwidth]{b}}; \draw[-&gt;] (A) to (B); \end{tikzpicture}     But I want the arrow to start and end right at the images with no space between. How can I do that? Is it worth encrypting email addresses in the database? What’s the rule for adding “-er” vs. “-or” when forming an agent noun from a verb? What’s the rule to decide whether you add -er or whether you add -or when creating an agent noun from a verb?    Sometimes it’s -er:      read > reader hate > hater hit > hitter   But other times it’s -or:    meditate > meditator collect > collector Is it possible to store user's crontab in user's git repository on OpenBSD? On OpenBSD and with OpenBSD's  and , is it possible to store the  of a user in a  repository of the same user?  What would be the proper way to accomplish something like this?  (To steer the answer into the correct direction, I would not be opposed to changing some permissions in the system, although I'd rather not have to recompile the binaries, nor violate any good security paradigms.) I've seen $d(xy) = y(dx) + x(dy)$, but I don't understand the principle behind it and memorizing it is lame.  Can anyone explain what is going on here?  For example from physics, $$F = {{dP} \over {dt}}$$ $$F = {{d(mv)} \over {dt}}$$ $$F = {{v(dm) + m(dv)} \over {dt}}$$ Since $$dm = 0$$  $$F = {{m(dv)} \over {dt}}$$ Since $$a = {{dv} \over {dt}}$$ $$F = ma$$ Is there a quicker way to turn on WiFi Hotspot? is there a way to automate (or at least reduce the number of steps) to turn on or turn off the WiFi hotspot on my Galaxy 3.  I have to    unlock  press the menu button  press settings press More Settings Tethering and portable hotspot Slide portable hotspot on. A book on quantum mechanics supported by the high-level mathematics 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).