The text boxes that were once OPAQUE prior to editing become Transparent after they have been edited. If the box is over an area with text or a pattern, the text will not be legible. Also the font changes to a sans script that is disproportionate and hard to read.
Restore the function to create boxes that were opaque and allow coloring the background of text boxes. Why would these features be removed?
If this is device related.. I'll add that my Note IV running Android 4.4.4 never messed with Reader prior to the updates of 2016.