I remember this issue already occurs (don't remeber if it was on MT4 or MT5 - I guess it was already on MT5). Each time I recompile an EA in Metaeditor if I swich back to Terminal and rerun the tester, it does not take in account modifications made. I need to reset the terminal. I probably missed something, but don't know what? It is very easy to test, just put a Print command in comment and recompile, the tester is still showing message in Expert log!
PS : I am using the /portable command not to use the roaming folder.
This is not when I am updating and recompiling the EA.
My EA include a mqh file placed in Include directory. That mqh file import a ex5 file compiled and place in MQL5\Librairies. I first recompile the librairy, then the mqh file and finally the EA file.
If I made modification to the EA file, no need to close and reopen the terminal but if I modify the Library even if I recompile the library then the include file and finally the EA : modifications made in the library are ignored.