Question: Maybe a bug in 2d-math?

Hi, when I use maple to calculate some complex equations, there maybe a bug in 2d-math, and the problem is surprising.

As the following illustrated, f4 is a large equation, and r4, a short one. If I put the mouse pointer at  f4 and press the "enter" key, then maple excute f4 rightly and the mouse pointer go to p16 directly.(It seem that r4 has been skipped), then I press "enter" key when the mouse pointer locates at p16, an error occured. It is clearly that maple dose not run r4.

The code seems like:

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f4:={f1(x,y)=0,f2(x,y)=0}:

r4:=fsolve(f4):

p16:=point([rhs(r4[1]),rhs(r4[2])]):

error...

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After some test, I find that a short equation will be skipped by maple if the short equation is followed after a big equation. So it is need concerning that the user use 2d-math in maple, especially the equations are complex and large.

P.S. Can anyone tell me how to upload a picture if the picture has not a url?