Unvisible usergenerated text

After the last update of theme Responsive (2017-08-29) on the site https://seniornet.se user-generated text in loginfields, forum and chat became invisible, i.e. had the same color as the background.

I have been in contact with a person in the Swedish WordPress forum who had the same problem with his wp-site. However, in a test version of my WordPress-installation (https://u8276913.fsdata.se/) with theme Responsive and the same plugins there was no problem.

I have temporarily solved the problem by changing the color in style.css at row 3053 to #000000 instead of #f2f2f2:

.contact_right select, input[type=”text”], input[type=”password”], input[type=”email”] {
width: 100%;
color: #f2f2f2;
padding: 12px 2px 2px 0px;
background-color: transparent;

On the testsite where there were no problem the color is still #f2f2f2.
Therefore the invisible text-problem has to be located elsewhere.

I hope you can find the root of the problem.

Regards,
Gunilla