Dark Brown

You need to be careful when using this color of LEGO part.  In the past this was one of 3 colors that was a little bit more brittle than others, and would tend to break if one was careless during the removal.

However, according to the LEGO group, they fixed the problem in 2018, but there are still millions of pieces out there that may experience this.

The three colors that had this problem are154 (New Dark Red), 192 (Reddish Brown) and 308 (Dark Brown).

To help with the problem use the orange LEGO tool.  While not guaranteed to prevent breakage, it can significantly help.

Of course, because LEGO has amazing customer service, if you do have a piece that breaks, just contact LEGO and they will send you a free new replacement peice.