NEXXT 3.3.1 - "seams checker", selection aware sort actions, and more

I've just uploaded v3.3.1 to itch.

Hotfix:
3.3.1: 3.3.0 started erroneously started on the tiles tab (it should be the screen tab). I snuck this hotfix in to avoid confusion. 

Bugfixes

It fixes several user-reported issues, namely 2 reasons for crashing while importing images; using "lossy tiles" mode,
and 3 bugs while drag-dropping a group of tiles to swap places.

New features and improvements

There's a "seams checker" mode for the CHR editor (see the header GIF for this blogpost). With it, it's easier to check for continous seams in patterns that are meant to be repeated continously. The shortcut to toggle it on/off is [Alt+G].

I've also added the *.dmp extension to the defaults when importing a PPU dump, so there's one less click each time to do for Mesen (emulator) users.

Sort tiles by Frequency, Density or Detail has now become selection aware. That means as long as you have a box selection, or consecutive multi-selections, these Sort actions will only sort tiles within the selection.

This is especially handy for when managing banks smaller than a full tileset, or when you simply want to exclude certain tiles from the sorting (such as font set, GUI elements, or the like).

The 'gradient strip' and the 'pattern paint'-mode has gotten their own combined breakout toolbox. Currently, it collects colour filters (decides what colours from a pattern to draw or ignore), something called 'mask mode' (uses the colour filters to use a pattern as a mask for drawing the pen colour instead), and tool filters (gives fine control over what tools are affected when in 'pattern paint' mode.

All are enabled by default, as to be intuitive, but personally I like to disable "apply to pen" and occasionally "apply to line", as to reserve it/them for fine detail work without having to exit pattern paint mode.

More 'pattern paint' toolbox controls are coming, not least allowing you to choose user-defined patterns and not just the gradient strip as source - but that didn't make the cut this time.

Special thanks 

To Sarah (potatolain) and hunterpage27 who've donated or joined since last version update. 
To M-Tee and ToffiRola who've taken their time providing me with high quality issue reports, which are now resolved.