Interestingly, if I run your code in a live script, it initially renders incorrectly, but then corrects itself. If I run your code here, it renders misaligned.
I think a reliable way to create this figure so that it renders the same everywhere is to update your code to use tiledlayout and boxchart.
G = rand(1,7*15);
noa = ones(1,5);
nob = repmat(2,1,5);
noc = repmat(4,1,5);
no = cat(2,noa,nob,noc);
figure(5)
t = tiledlayout(2,4);
title(t,'Fracture Energy vs Height')
% Titles
tph = ('3Dd1s1 d1s1 d1s2 d1s4 d2s1 d2s2 d2s4');
tph = split(tph);
G_sub = 0;
for i = 1:length(G)
if rem(i,15)==0
G_sub = G(i-14:i);
nexttile
boxchart(no,G_sub)
title(tph(i/15))
xlabel('Height [mm]')
grid
end
end
