Tools and techniques for downloading images

To redirect downscaled images to their original version, or replace all images
in a page with their original versions, use Image Max URL. It can then be
combined with DownThemAll to mass download all original images. (firefox extension) (usescript version, for other browsers)

To rip image galleries, use a dedicated crawler like gallery-dl, jdownloader, wget.

For tistory in particular, use tistore:

For, see:

To mass download pictures using your browser, use the firefox extension
DownThemAll or an equivalent, like Download Star.

You can also use uget, which is an external download manager that integrates
into firefox:

To rip photographers' photos from twitter, you can use Twitter Media Downloader (available as firefox and chrome extensions, and also as a userscript).

To run userscripts, you'll need an extension like Violentmonkey or Tampermonkey.
Chrome users can also install userscripts directly.

To install userstyles, use Stylus.
Guide to importing userstyles:

To open images in new tabs using mouse gestures, see this guide:

To use daum for getting higher res pics from some news sites, see this guide:

How to search naver for news articles:
Note that the daum guide above was made from the same /hr/ posts referenced
at the end of this naver guide.

For loopvid userscripts that perform parts of what Image Max URL does (allow
mass downloading, redirect images to originals, allow right-clicking on
instagram, rename url-quoted filenames from tistory), see this guide: