Hi Lovro, Thanks for filing. I see one or two flickerings / delays too. Not so much, but it is visible. Is that what you mean?
It looks to me like too much refreshing of the box with styles and formatting is done. I think two or three, while only one is required. Furthermore, it could be that the whole tree is firstly closed, then it opens again.
I have noticed this too (LO 5 RC 2 and 3, Win7 x64). It isnt just flickering - the listed styles move up and down if there is not room for all the styles in the visible sidebar window. This becomes a nuisance when selecting text and applying styles as the style list may still be moving when selecting the style - several times I have ended up choosing the wrong style because the list will not keep still, and this is on a 4790K so it is not an inadequate processor.
Dear Bug Submitter, This bug has been in NEEDINFO status with no change for at least 6 months. Please provide the requested information as soon as possible and mark the bug as UNCONFIRMED. Due to regular bug tracker maintenance, if the bug is still in NEEDINFO status with no change in 30 days the QA team will close the bug as INVALID due to lack of needed information. For more information about our NEEDINFO policy please read the wiki located here: https://wiki.documentfoundation.org/QA/Bugzilla/Fields/Status/NEEDINFO If you have already provided the requested information, please mark the bug as UNCONFIRMED so that the QA team knows that the bug is ready to be confirmed. Thank you for helping us make LibreOffice even better for everyone! Warm Regards, QA Team Sat, 10 Sep 2016 16:48:27 +0200
in LibreOffice 5.3 master there is a little check box at the bottom to have the list without preview. I think that solves the problem.