Hello,
It may be a problem with the Java you have installed.  Insure you have 32-bit JRE if using LO 32-bit or 64-bit JRE if using LO 64-bit.  Once installed, check the setting from menu Tools->Options then under LibreOffice->Advanced insure Use a Java runtime environment is checked. After a few seconds a JRE environment should display if you have a correct JRE installed.  Make certain it is selected - click on circle to left of Oracle Corporation.  A dot will appear in the circle signifying it as selected (there can be many JRE’s installed for LO).
Have tested this on LO 6.1.4.2 64-bit on Linux Mint 18.3 and works.  However, did have crashing in most selections when used with OpenJDK vs Oracle JRE.