v3.26.1
Share capital - Disclosure of PSUs and RSUs Shares (Details)
SFr / shares in Units, SFr in Thousands
 6 Months Ended
Jun. 30, 2026
CHF (SFr)
shares
SFr / shares
Shares Outstanding [Roll Forward]  
Number of treasury shares withheld to cover social security and tax liabilities (in shares) | shares 125,127
Total TCHF value at beginning of period SFr 1,129
Total TCHF value at end of period SFr 1,233
Treasury shares  
Shares Outstanding [Roll Forward]  
Number of treasury shares outstanding at beginning of period (in shares) | shares 2,962,973
Number of treasury shares, other equity-settled transactions (in shares) | shares (25,000)
Number of treasury shares outstanding at end of period (in shares) | shares 2,069,404
Average price in CHF at beginning of period (in CHF per share) | SFr / shares SFr 0.38
Average price in CHF, other equity-settled transactions (in CHF per share) | SFr / shares 0.28
Average price in CHF at end of period (in CHF per share) | SFr / shares SFr 0.60
Total TCHF value at beginning of period SFr 1,129
Total TCHF value, other equity-settled transactions (7)
Total TCHF value at end of period SFr 1,233
Treasury shares | PSU program  
Shares Outstanding [Roll Forward]  
Number of treasury shares vested under the program (in shares) | shares (873,552)
Number of treasury shares withheld to cover social security and tax liabilities (in shares) | shares 103,875
Average price in CHF, shares vested under the program (in CHF per share) | SFr / shares SFr 0.28
Average price in CHF, shares withheld to cover social security and tax liabilities (in CHF per share) | SFr / shares SFr 3.08
Total TCHF value, shares vested under the program SFr (245)
Total TCHF value, shares withheld to cover social security and tax liabilities SFr 320
Treasury shares | Restricted Share Units (RSU)  
Shares Outstanding [Roll Forward]  
Number of treasury shares vested under the program (in shares) | shares (120,144)
Number of treasury shares withheld to cover social security and tax liabilities (in shares) | shares 21,252
Average price in CHF, shares vested under the program (in CHF per share) | SFr / shares SFr 0.28
Average price in CHF, shares withheld to cover social security and tax liabilities (in CHF per share) | SFr / shares SFr 3.23
Total TCHF value, shares vested under the program SFr (33)
Total TCHF value, shares withheld to cover social security and tax liabilities SFr 69