Yes I know why this happens. Sorry I forgot to explain the secret behind that.
I’m not sure if it is a bug but I it might be and most probably is.
If I want the text on an entire tab To be be centred or left or right I don’t use several style tags. I just add all the different styles you could have in markdown inside a rich text and leave it at the bottom. When I’m adding new text it’s always in the middle on that tab. See we dummies know a few things (lol). Try replacing centre with left or right and it will have the same effect.
The reason you are seeing this effect is because I have used an increment button to give one tab the appearance of two tabs. Using the return home button I created the fiction of two tabs. When the button increments by 1 or - 1 The images remain as they are. Hence this effect.
It is most likely a bug 
as only markdown has this effect on the increment function. But it’s a safe one ! You can see the same on the dashboard too.
It’s the last component on the home tab. You can put it anywhere you like. It will even force text boxes aligned say left to the centre. It’s very useful. You can see some text boxes are aligned left but still centred on that page. Hope you find it useful.
Sorry meant to say fiction of two screens not tabs.