Please help us help you and fill where relevant:
Your LimeSurvey version: 6.5.5
Own server or LimeSurvey hosting: Own
Survey theme/template: Fruity
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We are testing out version 6.5.5 on a fresh install (part of a domain migration), currently using 5.6.35.

We have noticed that regardless of theme we use, the CSS class is half working when displaying the question. We want to have for example 3 text answer questions in a row, for these we have set the CSS class in the display options to "col-sm-4, col-md-4, col-lg-4" on each and whilst they are resizing they are not sitting side by side.

Any advice would be greatly appreciated.

It seems the issue with CSS classes in LimeSurvey version 6.5.5 might be from how they're applied or the compatibility with your theme's CSS. Plz make sure that "col-sm-4, col-md-4, col-lg-4" classes are defined correctly and compatible with Bootstrap grid. Check for conflicting styles and use browser tools for inspection and adjust CSS.

@andrlewis we don't really need IA answers.

getbootstrap.com/docs/5.3/layout/grid/