Created attachment 139765 [details]
Sample Base file - Two forms

Sorry, here is version tested with:

Version: 6.0.1.1
Build ID: 60bfb1526849283ce2491346ed2aa51c465abfe6
CPU threads: 4; OS: Linux 4.13; UI render: default; VCL: gtk2; 
Locale: en-US (en_US.UTF-8); Calc: group

Also used new user profile.

/cygdrive/d/sources/bibisect-win32-6.0
$ git bisect log
# bad: [fd9eaf386eee8b032c49084eba0a3034d28382b7] source 47cc374c0659fd3db74a1b184c870eaa56bc385b
# good: [cc5c4c7ed1d8d01b0063bcaaeb5f6d59282c8029] source 9feb7f7039a3b59974cbf266922177e961a52dd1
git bisect start 'master' 'oldest'
# bad: [1c90be7178d31c0f4cb17ff9e7c44a6cb9a2b058] source 029f2fdc2a164ca5ab2ecb9e2d4b9cf5112083b4
git bisect bad 1c90be7178d31c0f4cb17ff9e7c44a6cb9a2b058
# good: [ae948ca761402e6b70edb620a5de1b89cfe27f5b] source cc8390df26dad04a74425804dbd7ba068daca0c2
git bisect good ae948ca761402e6b70edb620a5de1b89cfe27f5b
# bad: [367a86a05abf865e3ed7d8cb533b1e2a827b1111] source 77f854f13033eeff3147dae1c5ffbfaf4eec93c1
git bisect bad 367a86a05abf865e3ed7d8cb533b1e2a827b1111
# bad: [4812f97372d983faddafacf89f8713a3ffcc5975] source be604957ecab49b1f4dfcfa468d572e0da549d3c
git bisect bad 4812f97372d983faddafacf89f8713a3ffcc5975
# good: [90d6d67de8b74dbfe07ce15e1b930506dc1d0557] source f65cbae8947c0462b35c8d3c3d5124e431b100b6
git bisect good 90d6d67de8b74dbfe07ce15e1b930506dc1d0557
# good: [b9fd2e5fd3a45ec77bd1f04b7482c7c34c3950be] source e47fda7d4759f4ac911c882881dba1eee539726c
git bisect good b9fd2e5fd3a45ec77bd1f04b7482c7c34c3950be
# bad: [4c86a45a8a9a0374c55c4ea45fc6473b9874042c] source 2c4c08320532d2edfbd53d1bb0c45e7448caf004
git bisect bad 4c86a45a8a9a0374c55c4ea45fc6473b9874042c
# bad: [e4858cafa3ed01093d9f3712c58713cf8675594b] source d6a16aedca28ad5a907104c02174abd88fb03aed
git bisect bad e4858cafa3ed01093d9f3712c58713cf8675594b
# good: [ac6da2879c5f160b51195053d1068074283232ea] source 39dd0121f5994dee56f95bc57fae3323bf849a20
git bisect good ac6da2879c5f160b51195053d1068074283232ea
# good: [2006cdbbbf263789119660949448301b1cc838d1] source bdbebda1d80f538f946b14042a366029f90d4820
git bisect good 2006cdbbbf263789119660949448301b1cc838d1
# good: [53cd0ea77358e5ea6f8933846afdfa4192290b10] source 94c7a401583200cf5982594b1b043ad1a5e3cd38
git bisect good 53cd0ea77358e5ea6f8933846afdfa4192290b10
# bad: [441a96d3066dd450a122056334646b8df458b251] source a35b17dd1768c39ffe786f38b1fe0c8be7666974
git bisect bad 441a96d3066dd450a122056334646b8df458b251
# bad: [8684144441c2e5c33ac879dfcaf98d022ce76cd5] source f9d5877f41b54882a7f364f33b314cbaeb3b44c0
git bisect bad 8684144441c2e5c33ac879dfcaf98d022ce76cd5
# first bad commit: [8684144441c2e5c33ac879dfcaf98d022ce76cd5] source f9d5877f41b54882a7f364f33b314cbaeb3b44c0

https://cgit.freedesktop.org/libreoffice/core/commit/?id=f9d5877f41b54882a7f364f33b314cbaeb3b44c0

> author	Szymon Kłos <szymon.klos@collabora.com>	2017-07-14 16:11:40 +0200
> committer	Szymon Kłos <szymon.klos@collabora.com>	2017-07-14 18:12:27 +0200
> commit f9d5877f41b54882a7f364f33b314cbaeb3b44c0
> tree 51aa7d7c3b09022fcce2a5f835e9d55db847f761
> parent 94c7a401583200cf5982594b1b043ad1a5e3cd38
> Embedded obj: don't change new window size

Adding Cc: to Szymon Kłos

This is still a problem. It exists with all released versions 6.*

I have a split system with the back end on Windows Server 2012 and on Centos 7. The front end is on Fedora F28, Linux Mint, Windows 10 Pro and Windows 10 Pro Insider. All combinations exhibit this REALLY annoying bug. Please do something about it. It makes my application almost unusable. This bug was raised in February 2018 and has still not been assigned. Please do something.

This bug, since originally reported, has gotten worse.  Sometime after reporting all form sizes are now of a system determined size which occupy most of the screen.  No matter what the form size is set to it will generate some default size (all the same size) for every form. Have no idea where this size originates from.

The only method to keep this somewhat under control is to use a macro to set the width and height.

Current version used:

Version: 6.3.3.2
Build ID: a64200df03143b798afd1ec74a12ab50359878ed
CPU threads: 8; OS: Linux 5.0; UI render: default; VCL: gtk3; 
Locale: en-US (en_US.UTF-8); UI-Language: en-US
Calc: threaded

Still appears to be an issue with 7.0.0.3 for Linux

What is the "size" of a form for you?
A form is in principle a text document. It has a page size, which you can change in menu Format > Page style in edit mode.
But a form opens in default in Web View. And in Web View it does not use its size from page style, but uses width and height of the containing window. And the last state of the window is remembered and used.

(In reply to Regina Henschel from comment #12)
> What is the "size" of a form for you?
> A form is in principle a text document. It has a page size, which you can
> change in menu Format > Page style in edit mode.
> But a form opens in default in Web View. And in Web View it does not use its
> size from page style, but uses width and height of the containing window.
> And the last state of the window is remembered and used.

This used to be true.  However for the last few years no matter how you edit and size a form is takes on a large size determined by the system.  Even with using macros to resize and position there are further complications.

For size used to be nice but there is no last state remembered anymore - not for years.