The following is for the CAN protocol decoder, but it may affect all protocol decoders. The 8ce0e732cfe912e022eb96d06aaaa40390efcd6b (2018-04-08) fix to PulseView (now again updates the display when a parameter to an applied CAN protocol decoder is changed, e.g. bit rate) seemed to have introduced a new problem: If the "Sample point (%)" parameter is changed then the protocol decoder reverts to using the default bit rate, 1000000. E.g. if the bit rate first has been set to 250000 then changing the "Sample point (%)" parameter will result in a effective bit rate of 1000000 (the display is updated immediately). (It is the same the other way around - if the "Sample point (%)" parameter is first changed to 1% and the bit rate is changed from 1000000 to 1000001 it reverts to using the default of 71%.)
I actually don't know if 8ce0e732cfe912e022eb96d06aaaa40390efcd6b introduced a new problem. The described problem could have been introduced earlier (like the display update problem that was fixed with 8ce0e732cfe912e022eb96d06aaaa40390efcd6b). All I know is that a nightly from end of December 2017 did not have any of these two problems.
Credit should go to IRC "keesj" (Kees Jongenburger, <http://keesj.github.io/A10-OLinuXino-LIME-5510-Shield/index.html>) for noticing this problem.
And IRC "L29Ah" - "PulseView goes nuts"
To be clear, the parameter appears as changed in the protocol decoder input field, but it is using another value, the default value, instead.
Fixed in c5f473341f9198532c44525104d04792c1bd6459, thanks!