Universities, significantly impacted by the shift to online learning during pandemic, must critically evaluate their teaching methods and outcomes to enhance performance in the post-pandemic era. However, there has been a limited examination of whether students achieved comparable levels in cognition and social interaction during the pandemic compared to traditional face-to-face learning. Addressing this gap, this exploratory study utilized a quasi-experimental design to analyse and compare the learning performance and outcomes of two cohorts of students (totalling 45) in a 12-week university course delivered through the computer-supported collaborative learning (CSCL) approach, both during and after the pandemic. Employing quantitative analysis and lag sequential analysis, the study examined students' behaviours, similarities and differences in performance within CSCL environments under two distinct social situations. Results indicated that students engaged in complete online learning with CSCL and those in face-to-face teaching with CSCL achieved similar levels of conceptual understanding. Additionally, a comparable distribution pattern of learning behaviours was observed. However, significant differences in behaviour sequences emerged between the two implementations, with students exhibiting a higher level of engagement in CSCL activities during the post-pandemic period. These findings inform the design of CSCL environments should integrate student-centred activities and include guiding scripts, prompts and scaffoldings in navigating learning endeavours effectively.