As stated in the title, when I open Settings and click on Privacy then Screen Lock all of the options are grayed out.    The Blank Screen setting in Power is set to 15 mins. Super+L is set in the Keyboard setting to lock screen, but never works. The only thing that seems to work is the Switch User in the upper right menu.  GNOME shell extensions:   User Themes System-monitor   $ xset q Screen Saver:   prefer blanking:  yes    allow exposures:  yes   timeout:  0    cycle:  0 DPMS (Energy Star):   Standby: 0    Suspend: 0    Off: 0   DPMS is Enabled   Monitor is On
Recently upgraded to Ubuntu 18.10, having two problems.  Easiest to explain: when I open "settings", go to "privacy", select "screen lock", I get the popup window with the screen lock settings, but everything is grayed out:   Second issue: If I step away from the machine for long enough (seems to be 5 minutes), the screen blanks. Hitting a key or moving the mouse wakes it up. But when it wakes up, the only things on the screen are the icon bar at the left and the top bar with status icons on the right end. The rest of the screen is blue, not my normal lock screen image. The screen isn't locked, it doesn't prompt for a password, it's just...blue.  I can move the mouse pointer around the screen, the icons react if I click on one, I can bring up the popup with volume/brightness controls on the top bar. But if the pointer is on the blue background, neither left nor right button clicks do anything.  Now, if I press ctrl-alt-F1 from there, I get a lock screen where I can enter my password. Then I get the blue screen back, but if I press ctrl-alt-F2 I get my normal screen (with running applications) back.  ctrl-alt-F2 without going through the lock screen first does nothing.  I'm not finding anything while searching that matches either of these sets of symptoms. Suggestions?
Why won't any faces show up in the UV Image Editor? I'd like to know if any certificates support a double wildcard like *.*.example.com? I've just been on the phone with my current SSL provider (register.com) and the girl there said they don't offer anything like that and that she didn't think it was possible anyway.   Can anyone tell me if this is possible, and if browsers support this? Get OS-level system information What is the difference between Set and SetDelayed? I will quote a question from my textbook, to prevent misinterpretation:     Let $G$ be a finite abelian group and let $m$ be the least common multiple of the orders of its elements. Prove that $G$ contains an element of order $m$.   I figured that, if $|G|=n$, then I should interpret the part with the least common multiple as $lcm(|x_1|,\dots,|x_n|)=m$, where $x_i\in G$ for $0\leq i\leq n$, thus, for all such $x_i$, $\exists a_i\in\mathbb{N}$ such that $m=|x_i|a_i$. I guess I should use the fact that $|x_i|$ divides $|G|$, so $\exists k\in \mathbb{N}$ such that $|G|=k|x_i|$ for all $x_i\in G$. I'm not really sure how to go from here, in particular how I should use the fact that $G$ is abelian. How to avoid spammy links affecting us before SERP rankings going down We have recently discovered a host of spammy links pointing to our website been put up in last 1 month through webmaster tool We have not engaged any seo agency/link building and have never created these links  Worst, these are spammy forum sites and almost some-one seems making an attack to our site as the link and keyword is same in all these sites Till not Have not received any warning, however as it has come to our notice - before any SERP getting down - we want to action this out  One thing we have observed is that - All these spammy links points to a single inner page of website  Pl suggest as have   a) Will Google disvow tool will work by stating to disvow these links  or  b) Is it a good way if we make this specific page 'nofollow' and even 'noindex' The reasoning behind this is like if the page is not followed and not indexed - the negative links pointing to the page of the site is already no follow and may be out from google serp  or what's the best alternate way to tackle this. Pl suggest in urgent help and advise required Cat5e cable has a rated current of 0.577A (). I am wondering if this is voltage dependent? I am almost certain it is not, but if it is, something might blow up. Say I need to get 2A at 5V across the cable. I boost it to 24V / 0.5A, send it across the wire, and step it down to back to 5V and a bit under 2A. Would that work? If the cable is proper Cat5e could I do this trick with up to 100V as long as I don't exceed 0.577A?   I am worried if the cable heats up at near maximum rated current, for instance, the safe voltage could drop as the insulation softens up or something. I will certainly test this, but I wonder if there is some rule that I don't know about. $SL_n(\mathbb R)$ is a subgroup of kernel of $f\in$ Hom$(GL_n(\mathbb R), A)$, $A$ is an abelian group. Try to prove the following proposition.     $SL_n(\mathbb R)$ is a subgroup of kernel of $f\in$ Hom($GL_n(\mathbb R), A)$, where $A$ is an abelian group.   My first attempt is to show that $SL_n(\mathbb R)$ is in form of $ABA^{-1}B^{-1}$, then it's clear that $ABA^{-1}B^{-1}$ is in $ker(f)$. However, there exists an elementary row reduction matrix, i.e. $E_{ij}(m)$ adding m times $j$-th row to $i$-th row. Then $E_{ij}(m)\in SL_n(\mathbb R)$. Now, it is possible that $E_{ij}(m)$ is not in $ker(f)$. Then I try to find any relation between $\mathbb R^{\times}$ and $A$, but, except knowing they are both abelian groups, I cannot figure out what else connects those two group. Could you give me some hints? If $p$ and $q$ are distinct primes , prove that $$p^{q-1}+q^{p-1} \equiv 1 \pmod {pq}$$     Using Fermat's Theorem we can get $$p^{q-1} \equiv 1 \pmod q, \qquad q^{p-1} \equiv 1 \pmod p.$$  After that I have no idea at all. Can anyone help me please Is a sentence always grammatically incorrect if it has no verb? Is the following grammatically correct? My friend says the second sentence is grammatically incorrect, but couldn't explain why.     I have always been fascinated by statistics. The different ways in   which you could look at data and infer knowledge from it. Can the relative pronoun "whose" be used for animals, things and countries? When I was a student of English as a foreign language, more years ago than I care to count, I was taught that the relative pronoun “whose” could only be used for human beings, i.e., when someone possesses something.   My teachers were native speakers from England, then.   Since that time, I’ve seen “whose”, as a relative pronoun, used in several contexts where no human beings are mentioned, e.g. with animals, objects, countries, abstract nouns, etc, in American newspapers and magazines. Unfortunately, I can’t remember any of the sentences and cannot give examples.  What is acceptable in written and spoken English, and what isn’t, concerning the use of “whose” ? How to provide a file download from a JSF backing bean? C Scanf suddenly stopped reading in values Comparison of backup tools How does rolling two d20 and taking the higher affect the average outcome? D&amp;D 5E has an "advantage" concept where instead of rolling 1d20, you roll 2d20 and take the higher. Likewise, disadvantage means rolling 2d20 and taking the lower.  How does this affect the expected average outcome of the roll? Understanding d-separation theory in causal Bayesian networks I am trying to understand the d-Separation logic in Causal Bayesian Networks. I know how the algorithm works, but I don't exactly understand why the "flow of information" works as stated in the algorithm.    For example in the graph above, lets think that we are only given X and no other variable has been observed. Then according to the rules of d-separation, the information flow from X to D:   X influences A, which is $P(A)\neq P(A|X)$. This is OK, since A causes X and if we know about the effect X, this affects our belief about the cause A. Information flows. X influences B,which is $P(B)\neq P(B|X)$. This is OK, since A has been changed by our knowledge about X, the change at A can influence our beliefs about its cause, B, as well. X influences C,which is $P(C)\neq P(C|X)$. This is OK because we know that B is biased by our knowledge about its indirect effect, X, and since B is biased by X, this will influence B's all direct and indirect effects. C is a direct effect of B and it is influenced by our knowledge about X.   Well, up to this point, everything is OK for me since the flow of the information occurs according to intuitive cause-effect relationships. But I don't get the special behavior of so called "V-structures" or "Colliders" in this scheme. According to the d-Separation theory, B and D are the common causes of C in the graph above and it says that if we did not observe C or any of its descendants, the flow information from X is blocked at C. Well, OK, but my question is why?  From the three steps above, started from X, we saw that C is influenced by our knowledge about X and the information flow occurred according to the cause-effect relationship. The d-Separation theory says that we cannot go from C to D since C is not observed. But I think that since we know that C is biased and D is a cause of C, D should be affected as well while the theory says the opposite. I am clearly missing something in my thinking pattern but can't see what it is.  So I need an explanation of why the flow of information blocked at C, if C is not observed. I read a comment under :     There are plenty of events that can occur that have zero probability.   This reminds me that I have seen similar saying before elsewhere, and have never been able to make sense out of it. So I was wondering    if zero probability and impossibility mean the same? if an event with zero probability doesn't mean that the event is impossible to occur, how probability theory represents/describes impossibility?   Thanks and regards! A projection satisfying $\| Px \| \leq \|x\|$ for all $x$ is an orthogonal projection How to prove that if $V$ is a finite dimensional inner product space and $W$ a subspace of $V$, if $P$ is projection map ($P^2=P$) having $W$ as its range and is such that $\|Px\| \leq \|x\|$ for all $x \in V$, then $P$ is orthogonal projection of $V$ onto $W$. Handling multiple regex matches in Ampscript Given this string:  SET @text = "&lt;a href=""https://salesforce.stackexchange.com""target=""_blank""&gt;Salesforce&lt;/a&gt; &lt;a href=""https://stackoverflow.com"" target=""_blank""&gt;Everything else&lt;/a&gt;"   And this function:  SET @matching = '\s+(?:[^&gt;]*?\s+)?href="([^"]*)"' SET @output = RegExMatch(@text, @matching, 1)   How can I manage to find and print an arbitrary number of matches in my string? E.g. in above example, I would like to present e.g. a rowset with each URL in each row. I recently installed Ubuntu 17.10, and when I tried to set my keyboard layout to change with alt+shift, I hit a . There is  which works, but then it creates an unwanted behaviour on Firefox (perhaps other programs as well).   After setting alt+shift through gnome-tweak-tool as the combination to change language, whenever this combination is pressed within Firefox, it triggers a toggle that Firefox uses to show/hide the Menu Bar (with File/Edit/View etc.), and 'focus' is taken away from wherever the cursor was.   It's very frustrating, because one has to go and click again at the cursor.  The only solution I found was to permanently enable Menu Bar in Firefox because then alt doesn't do anything and I can use it to change languages. But I don't want to have Menu Bar on top always.  I hope you can understand what I'm trying to explain.  Any thoughts?