Press F2 to open config file. Here all configurations is stored, such as the options you select in the righ-click menu.

Lock setting

Sometimes it can be useful to lock a setting so it will be the same att every start, yet you can change it during current session. Lock a setting by adding atribute lock="true".

Example: Blue background at every start but you can change it at current session (aslo see X11_color_names)
<add key="background" value="DodgerBlue" lock="true" />

Example: Always open full screen
<add key="rememberfullscreen" value="True" lock="true" />
<add key="fullscreen" value="True" lock="true" />

Hidden options

Not all options have been found worthy of a place in the menu yet, but can be found in the config file. Here is a brief overview.

Set default save format to jpg, png or tiff
<add key="default_save_format" value=".png" note="set to .png, .jpg or .tif" />

Automatically refresh image from file if changed by other software
<add key="refresh_image_if_edited" value="True" />

Change border color or hide it entirely (nice to combine with transparent background and F3, F12 options)
<add key="border_color" value="Transparent" />

Remove interpolation of images (if you are into pixel art)
<add key="scalingthreshold" value="0" note="zoomlevel when BitmapScalingMode is set to NearestNeighbor" />

Adjust this if swiping to next image on touch screen is not working well
<add key="swipetime" value="250" />

Change direction of mouse wheel image switch
<add key="wheelstep" value="0" note="-1 reversed, 0 no, 1 forward" />

Always show right-click menu when cropping (as it was originally)
<add key="block_crop_menu" value="False" />

Add this line to appSettings node and set a default save path instead of last used. Example value="C:\Users\you\Desktop"
<add key="save_path" value="your path here" note="Use Environment Variable like %USERPROFILE% "/>

Block feature

Add one of these lines to appSettings node and set it to True to block a feature. Also see Administrator options in How to
<add key="block_save" value="False" />
<add key="block_delete" value="False" />
<add key="block_make_gif" value="False" />
<add key="block_print" value="False" />
<add key="block_wallpaper" value="False" />
<add key="block_update_notification" value="False" note="Legacy installer only"/>