Created attachment 282566 [details]
widget factory screenshot showing inconsistency between cell render toggles and normal toggles

There's a few usability issues with checkboxes in gtk3-3.13.5-2:

1) Checkbox inconsistency

Checkboxes that are in GtkCellRenderers and checkboxes that are not in GtkCellRenderers look different (see attached screenshot from the widget factory.)

normal checkbox: has a box; empty box when unchecked; greyed when insensitive
cell renderer checkbox: no box; grey when unchecked; (??)

This is especially problematic in applications that have custom widgets that use checkboxes (eg Anaconda.) Some of our screens use the GtkCellRenderer checkboxes, and some (custom widgets) use the non-cell renderer checkboxes. 

Not only is this aesthetically problematic, but the inconsistently could cause users to question if the checkboxes are functioning properly and perhaps lose trust / confidence in the entire application.

2) GtkCellRenders checkboxes do not appear to be clickable

Since they are missing the box, they do not appear to be clickable. The lack of a box shrinks the apparent mouse target area. These checkboxes are also visually indistinguishable from the GTK stock icon for 'ok,' which typically is not clickable when used.

3) GtkCellRenderer checkbox states are difficult to distinguish between

Unchecked is a gray checkmark (no box), checked is a black checkmark (no box.) Not sure how a disabled checkmark would appear - a gray checkmark would be inconsistent since that already means 'unchecked.' Throw an active / selected row in the mix and things become very confusing. 

There are a number of scenarios in which it is difficult to distinguish whether or not the checkmark is actually checked or unchecked because the difference between gray and black is not all that great: consider lighting environments, LCD brightnesses / monitor settings, or potential visual impairments of users. When the first item in a list is active by default, it looks like the first item is unselected and everything else is (when they are not.) 

On my monitors, which are set to a pretty high contrast, the gray checkmarks appeared dark enough that I interpreted them to mean that they were 'checked.' Visually, it also looks very cluttered. Typically unchecked checkmarks have a blank box, so it's odd to see them 'filled' which I think contributes to the perception of clutter.


This may be related to bug #733967 but I am not sure of the context.