Radio slider - marking a response does not always work

URL of experiment:

Description of the problem: I created a simple picture rating questionnaire/experiment in which subjects are presented pictures and they have to rate it based on 3 questions. For each of the questions they have 5 answer possibilities, part where I used a slider (radio type). The experiment was constructed through the builder (Psychopy v. 2020.2.4) and then uploaded to Pavlovia.

Some participants told me that in order to give a response on the radio slider, they had to click several times on the same dot until the answer was recorded (and dot turned red) - sometimes they were not even able to mark a certain answer, despite multiple clicks. There were also situations in which it appeared as if they gave a response (dot turned red), but the response has not been registered in the csv file. The mentioned problem occurred independently of the used browser: the problem has been encountered on Chrome, Safari and Microsoft Edge (on multiple computers) and it occurred only in the online version.

Hello @MelindaSabo,

I believe I have just fixed the issue, which had to do with a strange behaviour when the experiment got into full screen.
My apologies for the mishap!
Best wishes,


Hi @apitiot, I tested it in piloting mode and now it works fine! Thanks a lot for your help!

I am facing the same problem (programming in Psychopy version 3.2.4) while running it offline. It’s a simple questionnaire with a yes/no option. Sometimes I have to click on the option multiple times before it turns red.