Reduced accuracy of millis with 0.5.0-rc.1 (ELECTRON)

I noticed Reduced accuracy of millis.
I do not know if the problem is up to the new firmware, but zablezhav that after each cycle 1 to 2 minutes get an extra second.
The program sends data to the server via HTTP every minute.
This is a block of a program, the program is a bit more complicated than just this but this section is of interest.

long previousMillis = 0;      
long interval = 60000; 

void loop(){
 unsigned long currentMillis = millis();

  if(currentMillis - previousMillis > interval) {
    previousMillis = currentMillis;




For example, if the data is sent in 1:00:15 next be sent to
1:01:16, 1:00:16, 1:00:17 and the like.
With the older firmware I have not noticed this problem.
Now I switched to using software timers and works great.
But better and another to make testing with simplest use of millis.