I’m using SliverAppBar with flexibleSpace:

SliverAppBar(
            expandedHeight: 280,
            pinned: true,
            leadingWidth: 44,
            stretch: true,
            elevation: 0,
            backgroundColor: context.colors.colorClubSectionAppBar,
            actions: [
              ...
            ],
            leading: GestureDetector(
              ...
            ),
            flexibleSpace: LayoutBuilder(
              builder: (context, constraints) {
                const maxExtent = 322.0;
                final currentExtent = constraints.biggest.height;

                _iconScale = currentExtent / maxExtent;

                return Stack(
                  children: [
                    FlexibleSpaceBar(
                      centerTitle: true,
                      collapseMode: CollapseMode.pin,
                      title: InvisibleExpandedHeader(
                        child: Text(
                          widget.section.name,
                          style: title3SemiBold.copyWith(
                            color: context.colors.colorTextWhiteFixed,
                          ),
                        ),
                      ),
                      background: Stack(
                        fit: StackFit.expand,
                        alignment: Alignment.bottomCenter,
                        children: [
                          CachedNetworkImage(
                            imageUrl: widget.section.background,
                            fit: BoxFit.cover,
                          ),
                          Positioned(
                            right: 0,
                            bottom: _iconScale <= 1 ? 80 : 80 * _iconScale,
                            child: Transform.scale(
                              scale: _iconScale <= 1 ? 1 : _iconScale,
                              alignment: Alignment.topRight,
                              child: CachedNetworkImage(
                                imageUrl: widget.section.extraIcon,
                                width: 170,
                                height: 170,
                              ),
                            ),
                          ),
                          Positioned(
                            bottom: 0,
                            left: 0,
                            right: 0,
                            child: Stack(
                              children: [
                                ClipRRect(
                                  borderRadius: const BorderRadius.only(
                                    topLeft: Radius.circular(16),
                                    topRight: Radius.circular(16),
                                  ),
                                  child: Container(
                                    padding: const EdgeInsets.fromLTRB(16, 12, 16, 20),
                                    decoration: BoxDecoration(
                                      color: context.colors.colorBase,
                                    ),
                                    child: Column(
                                      crossAxisAlignment: CrossAxisAlignment.start,
                                      mainAxisAlignment: MainAxisAlignment.center,
                                      children: [
                                        Text(widget.section.name, style: title25Semibold),
                                        Padding(
                                          padding: const EdgeInsets.symmetric(vertical: 12),
                                          child: Text(
                                            widget.section.description,
                                            maxLines: 3,
                                            overflow: TextOverflow.ellipsis,
                                            style: textRegular.copyWith(
                                              color: context.colors.colorTextAccentSecondary,
                                            ),
                                          ),
                                        ),
                                        Divider(
                                          height: 0,
                                          color: context.colors.colorOutlineStrong,
                                        ),
                                  ...
                      
          ),

But when I scroll up so that overscroll appears and the AppBar “stretches”, I see an artifact in the form of a strip like in the picture (Android only). For iOS it works fine. I think this occurs due to LayoutBuilder, but not sure. Please tell me the solution