As others have mentioned in this and other similar threads, the best way to avoid this problem is to use RGBA/HSLA or else use a transparent PNG.

The only thing that comes even close is the :contains pseudo class in CSS3, but that only selects textual content, not tags or elements, so you're out of luck.

A simpler way to select a parent with specific children in jQuery can be written as (with :has()):
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$('#parent:has(#child)');
***

With **\usepackage[hidelinks]{hyperref} ** you get active links in** \textcolor** (usually black) without a box around them.

TL;DR
*\textbackslash* produces a backslash in text-mode. The *math-mode $\sim$* and *\texttildelow* (from textcomp package) are options for a lower tilde (*while ~{}* and *\textasciitilde* produce a raised tilde in text-mode)

\input{filename} imports the commands from filename.tex into the target file; it's equivalent to typing all the commands from filename.tex right into the current file where the \input line is.

\include{filename} essentially does a \clearpage before and after \input{filename}, together with some magic to switch to another .aux file, and omits the inclusion at all if you have an \includeonly without the filename in the argument. This is primarily useful when you have a big project on a slow computer; changing one of the include targets won't force you to regenerate the outputs of all the rest.

\include{filename} gets you the speed bonus, but it also can't be nested, can't appear in the preamble, and forces page breaks around the included text.

The first account you sign-in as will be default
To set your default Google account:

Sign-out of all accounts
Sign-in to your preferred account; this will be your default

Add your hostname to /etc/hosts like so:
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echo $(hostname -I | cut -d\ -f1) $(hostname) | sudo tee -a /etc/hosts
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I also recommend using nvm instead, and also removing the already installed version to avoid conflicts in the terminal
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sudo apt purge nodejs npm
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then install nvm and use it

Just add the user to the sudo group:
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sudo adduser sudo
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The change will take effect the next time the user logs in.

This works because /etc/sudoers is pre-configured to grant permissions to all members of this group (You should not have to make any changes to this):

# Allow members of group sudo to execute any command
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%sudo ALL=(ALL:ALL) ALL
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As long as you have access to a user that is in the same groups as your "original" user, you can delete the old one.

For shutdown:
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sudo poweroff
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For restart:
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sudo reboot
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Ubuntu includes GNU tar, which recognizes the format by itself! One command works with any supported compression method, per the manual.
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tar xf archive.tar.xz
tar xf archive.tar.gz
tar xf archive.tar
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etc. If tar gives a Cannot exec error, you may need to sudo apt install xz-utils first.

You can print the status code, in addition to all the headers by doing the following:
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curl -i url
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The good thing about -i is that it works with -X POST as well.