While I was working on cartographic files (QGIS 2.18.16 - Linux Mint 18.1) using the rule-based styling window, suddenly the window and the program freeze and I can not longer work on editing. By closing and reopening the project file (and also other analogues other than those on which I was working) the problem remains (if i try work with the rule-based styling) even after uninstalling and reinstalling QGIS updating it to version 2.18.22. Opening the same files with version 3.2 the problem does not seem to exist. I would like to continue using version 2.18.x ltr up to the next 3.4 ltr, can this problem be overcome? Can it depend on the existence of a cache related to the rule-based styling window that is no longer accessible?
I add some informations: 1-it seems that the block occurs only when the rule-based styling window is open 2-the files I've worked on are on an external USB hdd 3-coinciding with this problem I detected the unwanted creation of a second mount point for the external USB hdd while the previous one was not accessible and with the root owner 4-also restoring the mount point setting as before the problem remain
Update 2018-28-07: I found that this problem was already reported as a bug here: https://issues.qgis.org/issues/16778 but I did not understand if it was taken into consideration or if we need to propose it again.