I use Fotoxx for montages and adding text and masking. Here I have an ice cream with a white background which I want taken out.

In Fotoxx Composite | Mashup |use current image file for layout and background image

as I already have Science magazine cover loaded.

Edit Images (add or edit images) | click Add Image and select the ice cream photo with a white background.

0.3 for the scale of the image. You can adjust the size this way. 1.0 is the actual size.

0.1 Base Transparency as I want it to blend in just a tad. 50% would be 0.5.

Click Var. Transparency Paint and you can adjust the Radius (size of circle) to paint to make it disappear. Once I finish painting transparency to the remaining white area it'll be complete.

I can add text by clicking Edit Text

To combine two or more pdfs together

pdftk first.pdf second.pdf output combined.pdf

or open first.pdf up with PDF Arranger or PDF Slicer and click + to Add second.pdf and choose Save As and name it combined.pdf

sudo apt install ncdu

ncdu lets you browse directories with arrow keys and ENTER key and figure out which ones are taking up the most space on a hard drive. ncdu from the directory or for your home directory ncdu ~

d key will let you delete the directory
now to delete that hidden .kodi directory which I deleted awhile back.

Also I was able to find out argos-translate is 5.2GiB installed and the cache is 4.4GiB..wow. Telegram Desktop cache is 3.9GiB

Czkawka can quickly search for duplicate files (took about 10 to 15 mins for me), big files (only 20 seconds) . Just download appimage.

LosslessCut export options. Merge all cuts together into one single video file. Keyframe is better if you don't need a frame by frame cut. Shift timestamps (make_zero) is important as it resets all segements to new time codes. If the original video isn't already optimized to x265 or just bloated then re-encode the merged video file in videomass.

Simon Tatham's Portable Puzzle Collection showing my favorite puzzles

Simon Tatham's Portable Puzzle Collection

Love logical puzzles. Great free puzzle collection.

https://www.chiark.greenend.org.uk/~sgtatham/puzzles/

Install on Linux Mint

sudo apt install sgt-puzzles

eyefoam ($free) https://hewgill.com/puzzles/

Simon Tatham's Portable Puzzle Collection

These are my favorite puzzle games in this collection which can be played online in your browser (javascript). I link to Nikoli (started in 1980) so you can see the original Japanese game it's based off of.

You can just hit SOLVE to see what the objective is and quickly read the rules.

Bridges, bridge-placing puzzle
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/bridges.html

https://www.nikoli.co.jp/en/puzzles/hashiwokakero/

Galaxies
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/galaxies.html

https://www.nikoli.co.jp/en/puzzles/tentai_show/

Keen, arithmetic Latin square puzzle aka KenKen
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/keen.html

Light Up, light-bulb placing puzzle
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/lightup.html

https://www.nikoli.co.jp/en/puzzles/akari/

Loopy, loop-drawing puzzle
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/loopy.html

https://www.nikoli.co.jp/en/puzzles/slitherlink/

Net, network jigsaw puzzle
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/net.html

Pearl, loop-drawing puzzle
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/pearl.html

https://www.nikoli.co.jp/en/puzzles/masyu/

Rectangles
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/rect.html

https://www.nikoli.co.jp/en/puzzles/shikaku/

Solo, number placement puzzle aka Sudoku
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/solo.html

https://www.nikoli.co.jp/en/puzzles/sudoku/

Tents, tent-placing puzzle with trees
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/tents.html

Unequal aka Futoshiki
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/unequal.html

For those on eyefoam or android there is a logical puzzle app I recommend. Free with banners / ads or ($7 to disable ads. I don't play that often so haven't paid).

100 Logic Games - Time Killers (also have volume 2 and 3 but don't recommend those just the first one)

These are my favorite puzzles from the game app.

Parks
Battle Ships
Thermometers
Hidoku
Hidden Stars

Nurikabe
https://www.nikoli.co.jp/en/puzzles/nurikabe/

Hitori
https://www.nikoli.co.jp/en/puzzles/hitori/

NumberLink
https://www.nikoli.co.jp/en/puzzles/numberlink/

Kakuro
https://www.nikoli.co.jp/en/puzzles/kakuro/

Other free to play puzzles in your browser are which I recommend are:

Logic Grid Puzzles
https://www.brainzilla.com/logic/logic-grid/
https://www.ahapuzzles.com/logic/logic-puzzles/

Zebra Puzzles aka Eisntein's Puzzle
https://www.ahapuzzles.com/logic/zebra/
https://www.brainzilla.com/logic/zebra/

Guess the Emojis
https://www.brainzilla.com/brain-teasers/guesstimate/guess-the-emojis/

Other ones on eyefoam I recommend
Honeycomb Hotel Free
Sherlock Free The Game of Logic (same developer as Honeycomb Hotel)
PathPix $2 (don't need the 15 other iterations of PathPix) this is good enough

I use Linux Mint XFCE which comes with Thunar File manager which has better regrex search and replace than Cinnamon’s file manager Nemo. You may want to install Nemo to easily create a SMB (Samba share) with another computer or your iphone. Right click on a folder in Nemo and create a share. Check guest access works too and ok for a home user.

sudo apt install nemo

Nemo also can search for files even with regular expressions (regex) and search for content within files. XFCE Thunar file manager can't even search for files.

Documents app (free don’t need to pay any IAP) can connect to the SMB share. This way you can upload files / photos / videos to your Linux Mint computer and download them to your eyefoam.

I said I only use two firefox extensions and that's mostly true. https://t.iss.one/geektips/104

I did need to use the excellent Down Them All extension to download about 400 mp3s from a website on one page. You can select the URL and it'll automatically add all mp3s and start downloading them. I'm gonna make an audiobook from it. 6GB to maybe who knows super small.

Down Them All — you can filter to only download images, music or videos.

In Fotoxx image editor you can edit the Custom menu just add the functions which are your favorites and used most often. These are mine.

Montage
Color Mode
Mashup
Crop
resize
Markup
Blur

sudo apt install deadbeef

DeadBeef is the only audio player that I could find that plays more than 132 chapters for m4b chaptered audiobooks on Linux. edit: qmmp also can but its a KDE app so avoid.

VLC maxes out displaying 132 and Cozy won't even add the m4b audiobook to its library let alone play it. Edit: Evidently Cozy eventually adds it and same problem as VLC only displays up to 132 chapters.

BookPlayer (free) on iOS is probably what I'll use to play these 132+ chaptered m4b audiobooks since DeadBeef can't even resume last played position (not for m4b audiobooks just perhaps from mp3s or opus music files). BookPlayer can show 1,138 chapters as I've tested it out previously.

sudo apt install cudatext

Cudatext is a text editor which I used to Shuffle Lines. I wanted to shuffle some videos to upload to a telegram channel just one per day.

GMIC-Qt 500+ filters. I previously mentioned to install GMIC as a Krita plugin. I much prefer it as a standalone app.

Just download deb file for Ubuntu 20.04 (for Linux Mint 20.3) gmic_3.0.2_ubuntu20-04_focal_amd64.deb
https://gmic.eu/download.html


To see an overview of all the filters GMIC 3.0.0 (released December 2021) can do see here
https://discuss.pixls.us/t/release-of-gmic-3-0/17226

Or here is the gallery from the homepage which I made into a PDF https://t.iss.one/geektips/160

Tried I believe all Linux PDFs readers evince, xpdf, qpdf and others and not one has dark mode. Rather just inverted mode which hurts the eyes at night. Also I believe if you have white text with a black background it’ll invert that which is exactly what you are trying to avoid. On iOS I believe Adobe Reader, Documents app and even Books Apple have dark mode.

Also Linux Mint 20.3 has a nice Notes app but unusable me as all the colors are super bright and it has no dark mode.

I spoke too soon there are two PDF readers that do have true dark mode.

Master PDF Editor is $70 but you can use the free version to enable dark mode. Works with text and scanned text (images).

Settings | Display and check Replace Document Colors
change Page background to almost black color and text to either white or light gray.

The free version can still annotate and highlight text but can't optimize PDFs (use ocrmypdf for that), watermarks, add headers, backgrounds, edit PDF text.
Okular (KDE PDF reader) but I despise it.

Best one I plan to use for night mode / dark mode is Zathura
No highlighting or thumbnails though.

sudo apt install zathura

nano ~/.config/zathura/zathurarc

Paste the following into the zathurarc text configuration file and save it. You don't need do create this configuration file as it already has dark mode CTRL-R but only do this if you don't want pure black and pure white colors.

set recolor true
set recolor-darkcolor "#dcdccc"
set recolor-lightcolor "#1f1f1f"

Keyboard shortcut keys since there isn't any menu

/ search for text
n next search result
shift+n previous search result

d toggles dual page display
o open another PDF
r rotate page
s fit to screen
- zoom out
+ zoom in
Tab show index
CTRL-P print
CTRL-R toggle recolor (dark mode)
F5 Presentation mode
F11 fullscreen

Add comic book support cbz cbr files and you can use dark mode on the images too
sudo apt install zathura-cb

edit: after using Zathura for a couple of weeks I really love it. I wish there was a show properties that's about it.