[BUGFIX] Admin panel text selection

Fixes: #58485
Releases: 6.2
Change-Id: I9c3243b2cca9edb89d262a4d3f9cde17b906d440
Reviewed-on: https://review.typo3.org/30118
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Tymoteusz Motylewski
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters